If your ping is 30ms, you don't notice it.
If your ping is 300ms due to say weak wifi, you do notice a 300ms wait when you open an app.
But the newer OSes do feel more bloated and indeed are sometimes slower. My 12-inch Macbook (low-powered dual-core i5) on Mojave feels much faster at opening built-in applications and simple tasks than my M1 running Monterey, and yet I can't think of any Monterey feature that I actually use over what Mojave already had - my workflow is exactly the same but now I seem to have to withstand a performance tax.
If you are on a high latency network, eg weak wifi signals, you'll be waiting 200-300ms.
Those on super fast internet don't notice, and think it's a problem with you, but no, it's Apple.
I live in a rural area, city under 40k. We don't have amazing internet.
Pretty sure this is only on first time launch to verify the notarisation.
It doesn't happen every time.