This kind of thing seems to happen really often.
I've not had a FB account for years, and didn't use it other than for messenger for years before that, but when I was on there, I felt that most of their growth came from 'copy what other sites are doing, extinguish the competition by doing this' strategy, as everyone is on facebook anyway. It's worked for them so far, just now it's a bigger shift to try to emulate TikTok rather than try to destroy local ads sites or small business site hosting.
That's because of unrealistic expectation from the stock market, not due to the company's health. A stall in user growth means a limit to the company size, and investors were betting that after the IPO Facebook (that was already used by a large share of the humanity) would still grow by two orders of magnitude.
But I think it's easier for them to centralise advertising operations where possible and steer the most malleable and lucrative audience rather than appease (what they thought of as) a minority of people.
they seem to be making a bet that existing users are addicted enough to the product that a change to it won't drive them away. and so far that seems to have worked for them.
May not have killed the golden goose yet, but they've sure sharpened the axe, stretched the neck over the block, and drawn a little X right in the middle.