Well, it is true I am not a businessman, and value creating something new and interesting far more than losing a bit of money. I’d rather have a reputation for making lots of new and interesting-looking stuff than a reputation only for pursuing strategies that serve the company first. I don’t care if that leads to failure, because if it does, people will still look back and say ‘those chaps were great, made loads of really different and new races’, as opposed to ‘gods those chaps were sods, keeping on releasing the same old nonsense just because they and a few other people like it’.
That sounds really nice, but to be fair, it isn't your money on the line. If you were feeding your family from the profits that GW generates, you might be singing a different tune. GW is a business and a business is there to make money. People's jobs and livelihoods are at stake.
If you create a business that makes "loads of different and new races", but they don't sell well, very few people will look back fondly on your company. Longevity is the key ingredient in creating such a sentiment. If you make consistent profit, then you are likely fulfilling the needs of your consumer base. As such, your company continues to produce products and you are able to bring in generations of consumers. GW has provided generations of fans with a great hobby because they were able to generate profit. If they had gone bankrupt 30 years ago, you probably wouldn't care to much about them today.
Unfortunately, upon dissection, your argument ultimately breaks down to "I don't like Empire, I like new stuff. GW shouldn't focus on Cities of Sigmar and make the new stuff I desire".
Besides, given that all the other AoS races GW have released so far have been moderately to highly successful and are continuing to generate profits for them all the time, a replacement for Empire would really have to bomb worse than anything ever previously released in GW’s history to make a significant dent in such profits, and if they developed this new faction cleverly enough to appeal to an already existing fanbase that was not satisfied with anything currently on the market, a loss could be quite easily avoided. It wouldn’t be hard for someone to investigate what other historical civilisation fanbases are kicking around online and find out which are the most popular, before designing this new faction to appeal primarily to one of those fanbases.
GW has far more information about the financial success of the individual races than we do. From that, they made a judgement call and now have to hope for the best. Whether or not this Cities of Sigmar army is successful, it was a choice based on the facts and figures they had available to them. We don't have any of this specific data available to us, so we really aren't in the position to make an informed decision.
What you are proposing is a choice based subjectively on your biased feelings against the Empire. What if it had been the Seraphon that were scrapped? To some people, the Empire is their "Seraphon". Frankly, with all the people clamoring for the Empire's inclusion, I'm surprised it has taken them this long.
A very similar Pro-Con ratio existed when they chucked out Bretonnia and Tomb Kings, yet that didn’t stop them from doing those dirty deeds and upsetting a good lot of people into the bargain, you included. It would simply be a case of ‘another one biting the dust’ in favour of progress
Obviously Bretonnia and Tomb Kings did not have the supporting metrics as Empire did. The fact that I like Tomb Kings infinitely more than Empire is irrelevant because the masses feel otherwise. Rest assured, if Tomb Kings had been an amazing seller for them, they would have stuck around. Consequently, the pros vs. cons list would look completely different from the one I provided earlier.
The trick is to separate our subjective feelings regarding the subject from the objective truth as much as we can. We all carry bias, but sometimes we have to push that aside and look at things from a more objective lens. I hate SCE, but they must be selling very well for GW and as such they should continue pumping them out. As much as I like to rag on GW, I can't really blame them for meeting consumer demand (though I might question the good taste, or lack thereof, of the consumers

). As I always like to say, we all get to vote, and we cast that vote with our wallets. Let everyone cast their votes and GW will respond accordingly. If most of the people end up feeling as you do, then eventually the Empire / Cities of Sigmar will fade away in the future. However, if it turns out that people like that army and want to purchase them, then your (or my) subjective feelings towards the army are largely meaningless.
yet that didn’t stop them from doing those dirty deeds and upsetting a good lot of people into the bargain, you included.
You can't include me in that group, as I couldn't be happier that Tomb Kings are not part of AoS! It brings me immense joy to joke around and state that Tomb Kings are not part of AoS because Settra refuses to bend the knee... Settra does not serve... and so on. I am happy that my beloved Tomb Kings have not been adapted and updated to serve the needs of a game that I despise. I don't want to see them twisted and altered to conform to AoS; I like them as they are.
Aside from some potential nifty terrain, I personally don't stand to benefit from TK in AoS. Their range in 8th edition is already largely complete (I have a Heirotitan conversion in the works). Any potential new models that might be released would not actually contribute to my WFB army in any significant way.
To be perfectly honest, the newfound rarity of the army only increases my love of my TK collection. If every single person on the planet owned a Ferrari, a Ferrari wouldn't be that special anymore.
Mind you, that these are my subjective feelings on the army, and has no bearing on my argumentation of GW's decisions from a business standpoint. If it made financial sense for GW to bring back TK, then I'd have to acknowledge as much, even if it flew in direct opposition to my personal feelings. However, if it was 100% up to me, TK would NEVER be brought back into AoS! Settra does not serve! (see how fun that is!

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