In the Hueco V-scale, V0 is supposed to be equivalent to 5.10 in the Yosemite Decimal System. But not a single gym I've been to sets V0s that are as hard as 5.10. Some gyms introduce a "VB" grade for beginners but their V0 is typically not as hard as the 5.10 they set on ropes.
I've always chalked this up (heh) to a need to make an enjoyable "first climb" experience for new climbers (who are typically messing around on boulders to see if they like it before learning to belay). If you start bouldering and can't even do the easiest problem in the gym then it's unlikely you're going to have fun and come back.
Unfortunately this leads to disappointing (and in some cases, dangerous!) first outdoor experiences since you try out a V3 and get absolutely shut down because your gym's whole rating system is biased by 1-3 grades.
I like the recent trend at most gyms to let members rate routes on a 5-star scale. You start to recognize good setters and climb their routes first. I wouldn't call it "setter worship", but good setting is something I can appreciate.
our favorites are chosen mostly because their grades feel right, and their climbs are fun. I see two problems that setters fall into: 1) make it super hard technically/hard to figure out, or 2) really easy technically, but you have to be the Hulk to get past it. someone that can balance those issues makes a good setter.
I think this explains the rating "deflation" where there aren't really any V0s because there is so much pressure to be known as a "hard" setter? Or possibly the dedicated setters are so experienced they don't remember what a V0 actually is? Either way I've found it to be an issue when trying to introduce climbing to novices.