you're comparing lightning networks to paypal. if lightning networks had the barest resemblance to paypal they wouldn't be worth discussing here and would not have been developed in the first place. i truly can't believe anyone who's been here a while would make this comparison.
lightning networks do have the potential for centralisation just as bitcoin or bcash does, but it's not baked in and people can work to make sure it's not a certainty.
Paypal process transactions thru their internal system.
LN process transactions thru their internal system.
Paypal requires a deposit of funds.
LN requires a Time Locking of Funds to act as a deposit.
Either way you have to withdrawal or wait for the time lock to end to get your funds.
Paypal can confiscate your funds.
LN Watch Towers can confiscate your funds, if an old transaction is broadcast.
So really no difference, both 3rd party processors, you have the illusion that LN can't take your funds , but in certain circumstances it can.
Research it, if you need proof.
Good Morrow.