We would need to poll for this as well if we were serious about applying hard scientific method.
Since the Strahd Poll, it appeared that we've had more frequent events run or supported by DMs between now and then.
It could be because the people have spoken or it could be mere coincidence (but then we'd be admitting the statistics are imperfect if we allowed the latter to be true).
It's most probable that the statistics are imperfect and we have no evidence to the contrary (and probably no evidence that DMs are more active now). I think that even if you get 70 votes saying satisfaction has lowered and 20 votes saying that's not the case, those results won't be adequate to account for all the people voting on the matter of anecdotal evidence and pure coincidence.
Just seems a shame that we desire certain Barovian factions to uphold the setting and the atmosphere of the area but they're frequently put in laughable situations of conflict with other characters they in no way shape or form can stand up against in PvP.
I think the problem is the way the PvP may be conducted, but that's for a different thread.
It's easy to say that the Garda are cultivated to be a faction of defenseless victims because of this cap, and that they're not adequately rewarded for their long-term commitment to roleplay in the region they're stuck with. It's not easy to say whether the cap is responsible for this or not, since the reward is supposed to just be the roleplay, and the XP technically has nothing to do with it.
Also, it's possible to get to level 20 and then join the Garda, and that's kind of on the individual player to make that decision, but the decision is available. We might see less of what you're describing if more people did that.