You know the reason. A bunch of people were able to take home a lot of money because of that growth and now have the option to FIRE themselves whenever they want to shake off the stress.
That's the founder mentality that Y Combinator exists to leverage or encourage and it's ubiquity is what separates the prevailing 21st century technology movement from the nerdy, academic, UNIX-y movement that gave us GNU, linux, curl, ffmpeg, redis, etc
We got to watch innovative products get pumped full of helium until they explode with bloat and rent-seeking instead of accumulating a growing foundation of sturdy technical building blocks as we could have had on the other path.
AI now leads us into some new movement, the worst version of which a few model vendors protected by regulations absorb almost all technical accomplishment and lease it back out to everybody else, and the best version of which democratizes technical construction so widely that individuals can naively spin up effective solutions for the most idiosyncratic needs.
We'll see how it goes.