I haven’t really played it in a while, but last time I did, gameplay still prevented that. You were able to buy way too many of some things you are limited in using anyway, but things that would give you a boost in mass weren’t for sale. Only thing you can buy yourself out of is maybe 1/4th of the reasons to go outside, but you can’t really play without the other 3/4th, and I have never paid, nor been beaten by somebody that did…
Anyway, all that was at least 3 years ago, so I’m not vouching for any possible changes to the contrary right now…
But It would amaze me if they did make it pay to win now, though. Niantic was always very strict in fair gameplay when it came to Ingress…