> Bitcoin doesn't need merchant protection, because transactions are irreversible.

They first have to get confirmed and that can take a long time on BTC. Replace By Fee offers another attack vector on transaction finality.

Other than those two very important points, I completely agree with you.

This is true. There really isn't a built-in way to do chargebacks and in practice this can suck if you live somewhere where that is your only recourse if you get scammed.