With the dynamics that are happening in the USA with the regulation of bitcoin, I assume that US citizens will have no other options for purchasing bitcoin in any other way than from PayPal (or other companies providing a similar service).
Everyone using PayPal and intends to buy Bitcoin will have their details traceable to them. It's okay for people who don't mind but for those who are concerned about their digital footprint, then they should use some other decentralized services where KYC isn't required.
Also, for many people (for example, the elderly and uneducated), buying, storing, using bitcoin is something extremely complicated and therefore, such people will be very happy to use the services of intermediaries, like PayPal. Which, in a way, also act as a guarantor of security, which will be taken advantage of by their clients who want to shift responsibility to Paypal.
I don't see any difference between this and buying a Bitcoin ETF. Paypal has been known to lock users accounts ( I don't know if they have changed) who speak ill against them on social media or online.
One thing I am sure of is that PayPal will certainly have clients for this type of service.
Surprisingly this contribute 0.1% to Bitcoin adoption even though I know US users have been buying Bitcoin through PayPal. This collaboration with moonpay is an added advantage.