The site is suboptimal, it's probably not a great company and I have no idea if they're charging me anything - but the one-tap purchase system just works, and that's all I need. There are other great options in Klarna and similar, but even they give me too many options to coax me into paying later so I inadvertently pay fees. PayPal literally just withdraws from whichever card has sufficient funds at the time, has worked exactly as stated for over a decade, so I really have no incentive to investigate alternatives (especially for sites where my PayPal is already setup, like Steam).
no alternative thou that manages adresses, confirmation and the actual transaction with one login/button
Countries with low consumer trust.
If it opens in a new window, it always seems to error out
I'm in Germany and order at a lot of specific sites, and while I don't like PayPal as a company or their fee structure, it's usually what keeps me sane. Most cases I don't have to enter anything, no need to create an account or even enter the delivery address. Doesn't get much more convenient than that.