Nah mate.
A lot of what you're saying is right but that's plainly and obviously wrong.
D&D isn't "trad fantasy" in the sense of "fantasy from 50 years ago". It's "trad fantasy" as in "mainstream fantasy".
Just look at D&D's art and how classes and so on have changed over the years. The issue that WotC's lead designers for 5E (specifically - not 3E or 4E) are slightly out-of-touch fantasy-wise. Not that a magic-warrior class isn't appropriate. It absolutely is - and even 3E recognised that. So it's been a lot of years.
I agree that it was improved, but it's still a totally trash conception of what a Bard is, and the changes were band-aids to trying and shore up this crap class, rather than a revision out of the terrible concept of "man who sings and prances during combat to make you, a real character who actually does stuff, roll higher", which as I said, was some appalling videogame rubbish even in 2000 (c.f. numerous videogame bards of the era, not least the EverQuest one from 1999, which seemed to be the largest single influence on 3.XE's take on the Bard). "Sneak, sneak, sneak!" was not unfair satire. And making them roll MUCH higher instead of just higher is exactly the wrong kind of improvement, because it shows a commitment the fundamentally dumb approach.
Also it's all very well saying everyone "should be" at T3, but they weren't lol. If Bards were "like 3.5E" in 5E, they'd be reduced to be a trash-tier joke character who stood around buffing people whilst real characters did actual actions with those buffs. Fortunately 5E's designers were too smart to fall into the trap of letting some characters be basically "buffbots" as they used to be called.