I think "fixed" is an overstatement. 5E changed it, just like every other edition has changed it... moved some numbers around, adjusted the refresh rates, shifted the balance a little to the left or right. I like the 5E version best so far, but i hope they aren't done tweaking it.
It's an overstatement you'll hear quite a lot though. Perhaps not vociferously on this forum, but on others, I've absolutely been straight-up told that 5e nerfed casters hard enough that any disparity that might've existed is gone.
As for the poll itself: the overall results more or less reflect my expectations, though I'm a
little surprised that Cleric did better than Bard (purely because the latter, as the literal and figurative Jack of All Trades, is the easiest class to bend toward a specific niche outside its normal one). Yes, Clerics have their domains, but IMHO you don't get nearly as much variation from domains as you do from Bard Colleges.
Also a tad surprised that Paladin and Warlock are only barely above the pack. The former isn't as flexible but offers both strong mechanics and interesting flavor (a group of knights from different faiths adventuring together for a common cause), while the latter has quite high flexibility and having everyone on the Warlock's short-rest recovery would significantly improve the class's balance. With the advent of the Talisman pact, you could even have nearly every party member using very different rules, e.g.:
- Two Chain warlocks with different patrons (pick two of Fiend, Celestial, or Archfey)
- Talisman + Genie warlock
- Hexblade + Blade Pact, for obvious reasons
- Tome + GOO (or Archfey, if it wasn't used for the Chain warlocks)
If the group goes out of its way to avoid too much stepping on one anothers' toes in terms of spell selection, you could have some very interesting stuff here. I could also see doing one Chain and two Tome pacts, as the Tome grants greater spell flexibility (so you don't necessarily need to have
every warlock using Eldritch Blast). Would work perfectly fine on its own and offer some very interesting flavor (what brings together such an unusual mix of loyalties?), but with just the lightest touch of useful homebrew (e.g. one or two custom Invocations for each character) you could easily turn it up to 11.
Perhaps I'll have to keep that fundamental idea--four or five representatives of powerful figures, brought together by their patrons' plots but finding camaraderie and internal loyalty along the way--for a future campaign, whenever my current one expires. I doubt I'd run it in 5e, but as an explanation for a 13A party meeting up, the idea has legs...