I think that the discussion about rogues being able to match & exceed wizards in knowledge skills is getting lost in the weeds so to say. You are very unlikely to see a rogue or bard giving expertise to all the knowledge skills your right, but one of them that is deeply important to the campaign (ie religion in an undead heavy ravenloft game) is not unheard of & probably more than adequate. Being the guy who knew stuff was only a very small part of what 3.5 wizards did great & not a very important part at that for reasons someone pointed out earlier, much of it was often plot related & the gm needed to find some way of getting it to the party for the game to progress.
If we were back in the days of 3.5 talking about this when wizards had so many other great pillars of practically unmatched awesomeness still propping them up as a class you'd be making a very reasonable point... but we are talking about 5e and all of those pillars of awesome are pretty well duplicated by others who still have their own pillars of awesome while wizards are still being told "well you have spontaneous casting now... just like every other 5e caster". Nobody is saying that it's bad those other classes have improved, just that it's bad wizard is pale & lacking in luster. You'l probably see more wizard multiclassing now that artificer is also an int based class, but wizards wisely did something they never did with sorcerer or warlock & did the sanity checking needed to make sure they didn't put in front loaded multipliciative abilities like scor/locka/din combinations so that won't really do much for that lack of luster. Doing thing like changing cantrip versatility to onRest & adding the ritual tag to a bunch of spells will however help with it to some degree.