I don't see the relevance of my info, but I can say I'm in my late 20s and work as a full time librarian. I also DM tabletop and post-by-post rping as hobbies. I have a preference for stout and porter with raspberries.
I won't speak for others, but I find balance to be important because I don't think people should be disadvantaged simply for creating a character they want to play.
This is something D&D has always been pretty bad at, greatly favoring certain classes and races. This is both baseline and specific combinations. 5e is probably the most balanced edition so far, but it still tend to favor casters and, for example, (standard) human is very underwhelming compared to other options, especially half-elf.
More than that, a certain balance in loot matters. Every weapon based character should be able to find gear fitting their playstyle and roleplaying. Arcane Trickster, for example, has 3 useful guaranteed drops around the Blighted Village (steelforged sword, warped headband of intellect and the faded drow armor. All are loot, not purchased).
A Strength based Fighter (or Ranger Knight), on the other hand, has a bit of a problem with getting armor that is even just decent. Going with 10 dex on a heavy armor character is supposed to be a perfectly reasonable choice in the system. Yet, until the Underdark, I've not found heavy armor better than ringmail (14 AC), which is just scale armor without the option to add dex to AC (14 with a normal max of 16 AC). So these characters are playing at a needless disadvantage for a significant portion of the content because of loot imbalance, despite chainmail (16 AC) being regarded as common enough to be starter gear in 5e.
Rogues have gotten a bit shafted compared to tabletop, losing Expertise and making Sneak Attack a declared mainhand attack rather than something added to either a mainhand or offhand attack. But they also got the option to flank without allies through Backstab positioning, so we can count the loss of Expertise as the only real nerf. Why does this matter? Because of Ranger and their access to Thieves' Tools. I like the update to Rangers, but the advantage of Rogues (and Bards) compared to other skill based characters is Expertise.
I'm rambling at this point, but the main point is this; games should be balanced in so far it gives every character a reasonable baseline to start with and work towards. No system will be perfectly balanced, but that is no reason to ignore the imbalances that can be addressed. All races, classes and archetypes should be desirable in some mechanical way both in and outside of combat.
