Okay, so here's my take on it based on my first day really interacting with the gym system, raids, etc.
Yes, spoofers have not been eliminated and they still have the distinct advantage that comes with not having to walk everywhere. But the important change that the gym system has brought, that in my eyes makes spoofing much less of an issue for the regular player is this: With how the coin rewards work by now you want your Pokemon in and out of gyms within a few hours (max daily coin rewards can be reached at somewhere between 8 or 9 hours defending with a single defender ). I'm currently actually a bit annoyed with a gym I placed my Vaporeon in yesterday still being up, because a) I'm not seeing my coin rewards yet, and b) when it comes back I'll get a maximum of 50 coins from it, even if it stays there for another few days. There's simply no more big reward for the things that spoofers can do much more easily than regular players (keeping gyms up for long amounts of time, placing in a lot of gyms all over the place, etc.)
The whole system feels so much more active and interactive to me now. I can easily solo even full gyms with defenders that start around 3000CP (and with only one of each Pokemon being allowed in a gym there's usually one or two of those high CP mons and the rest at around 2500 or even under 2000). It takes time to take them down, yeah, but at least it works at all. And not just for high level players, but also for casuals like me, giving spoofers potentially a ton more competition. Plus, if my 'mon gets kicked out I can just go out, retake the gym, place it back in and keep collecting coins.
So while the system isn't perfect by far, I think what really helped to level the playing field is that they are rebalancing how coin rewards work. If max daily coin rewards are possible for any player who can invest an hour or two of playing a day, spoofers may not be eliminated, but they just won't bother me nearly as much anymore, because they don't really hinder my own interaction with the gym system anymore.