DC inflation in printed modules wasn't your argument before (we can just scroll back to the threads I responded to). If that's what you meant, instead of there being no complaints about expertise in general or grappling in specific, then, sure, there's no DC inflation in printed material.
It wasn't my arguement, just one that I saw in this or the other thread - that these feats will cause DC inflation. Since expertise hasn't, I'd say that's a pretty moot issue.
Look, I look at it like this. If I tell you that I'm having problems with CR system in 5e, no one will bat an eye. That's a known issue for people. Whether you or I particularly agree with the issue isn't the point. It's an issue and you can point to a dozen different threads where it is being discussed.
Or, if I say that I'm having a problem with the stealth rules in 5e. Again, finding a dozen or so threads about this isn't much of a challenge. It's a known issue with the system. Again, not my particular issue, but, it seems to cause consternation among some people.
Or, as another example, the Sharpshooter or Great Weapon Master feats. Hardly a week goes by without someone bringing those up as a problem in their game, and some potential fix. Fair enough. It's a known issue.
But expertise? I read the forums pretty often. To be honest, this is the first time I've ever seen anyone complain about expertise at all. Maybe I just missed things in the scrum, but, it certainly doesn't seem to be much of an issue for people. I mean, I just Googled Jeremy Crawford's Twitter feed using Expertise as a search keyword, and it came up with a few very recent tweets about this particular UA Article, and a bunch of stuff about Crossbow Expert.
Like I said, if this is an issue, where is the evidence of it being an issue at the table?