Why is Paypal terrible? (Honest question, I find it to be a great service. Am not US-based, if that matters.)
They lock accounts on a whim and require extensive, unnecessary documentation to get your own money back. They recently settled a class-action suit because of this: https://www.accountholdsettlement.com/
They nearly always side with purchasers and reverse charges despite ample evidence supporting the seller.
Not to mention that currency conversion is a complete ripoff. I avoid PayPal like the plague.