FIRE: Thoughts on Withdrawal Rate

I've been reading here a lot lately that people are being advised against withdrawing 4%. Far too unsafe, doesn't work in the long term, especially over >30 years and at the same time some report that they are aiming for a withdrawal rate of 2.5% to 3%. That seems extremely pessimistic to me, or worse: you're probably working significantly longer than necessary if you're aiming for 2.5%. But maybe I'm making a mistake in my thinking, so I'd like to discuss this with you