I think the question I want to ask is: Why didn't Intel release these multi-core with hyper-threading chips sooner? It's like as soon as AMD showed signs of life with the Ryzen 2000 and now Ryzen 3000, Intel is saying "OK! Time to put more cores on our chips!" and then they flipped a switch and did it. Don't they have to prep their fabs or however CPU production works?
That or Intel has been preparing for a while and has decided now is the time to start leaking things out.
Your answer is capitalism. They aren't going to push the envelope too much unless they have to because it just means they would run out of room sooner on their current manuf capabilities. Also, Intel needs this out there in the world right now to give people a 2nd thought before plopping down the cash into AMDs ecosystem.
I know that the last time I did a serious upgrade was in early 2014, and I don't really need to upgrade now but just have an itch. My next rig I'm expecting to last about as long, and there have to be a lot of people just like me....Intel wants to keep these customers.