I think that is a bit unfair. Scoring is certainly up so the save percentages won't look as gaudy of course, but active right now I'd say Vasilevskiy, Saros, Hellebuyck and Shesterkin have all proven themselves to be damn good Goaltenders, and are all under 30. Ullmark is having a terrific season, but since it's his first big one, I understand wanting to see a bit more before throwing him in as well. You can throw Sorokin also in the pile of "looks good, would just like to see a few more seasons of it". Given their relatively young ages, it's hard say how they might stack up on all time level when it's all said and done.
I think you can say there was a definitely a bit of a lull of Goalies born between 1988-1992, so maybe that's where the perception comes from as those guys should basically be the ones that have been running the past few years. Of players born in that five year span, it's guys like Bobrovsky (2 Vezinas, but very up and down) and Holtby (Vezina and a Cup, but not a lot of longevity) carrying the torch. And then you got.... Frederik Andersen, Semyon Varlamov, Martin Jones, Steve Mason, James Reimer, Jacob Markstrom, Jake Allen, Jonathan Bernier, Darcy Kuemper and Robin Lehner rounding out the Career Goaltender Wins list.
For a fairly large swath of time (5 consecutive birth years) that's rather unremarkable.