This is what is being missed in the centralization fear mongering. Because of the way Bitcoin is structured even with further centralization it is still relatively easy for SPV light wallets to verify for themselves the validity of a payment to an address they control. The two ways to attack this are either 1) block re-orgs which require 51% style attacks or 2) creating false header chains (hard) plus making sure the SPV wallet can not connect to a single honest node (very hard).
I'm actually fairly annoyed that I have to be the one to create and publish a realistic and accurate Bitcoin threat model, because trying to create a privacy threat model is enough work on its own, and there are plenty of #bitcoin-wizards who could do as well or a better of a job.
Plenty of people have the ability put out accurate and objective information that could clear away the FUD and let us have a rational debate, but nobody else is apparently willing to do so.