What I think me and some of the other posters are saying is that clearly there is a line to be drawn SOMEWHERE between ultimate player choice and freedom, while maintaining balance and difficulty. It’s just that we disagree on where that line is. I like having a game, looking at my toolbox of options, and finding a creative way to solve the puzzle in front of me. If I need to enter the Drow base up ahead, I might use disguise self to look like a Drow. But now, I could for less resources, go and just change my race to Drow. I won’t, because that’s cheesy as hell, but the mere fact of knowing the ‘best’ solution was a dumb one that I intentionally didn’t use so I didn’t break my immersion, bothers me.
It’s the same reason some people don’t like barrelmancy, because it’s a narratively unsatisfying but extremely effective way to beat encounters. I come across what’s supposed to be a difficult encounter, I look at it like a puzzle, and go well I know I could just beat it with barrels. Or changing my class to wizard for this specific fight. Or using stealth cheese, or using double spells on Sorcerer even though that’s not how it’s supposed to work or or or…and sure I could just not use these. And I won’t, but the mere fact of them existing still makes the experience worse for me. That’s why I at least am bothered by changes like these.
These are different things. I mean, it should be clear to everyone that respeccing is a gameplay convenience and not an in-world power, that race changes do not happen in-world as a rule etc.. so it should be regarded as inappropriate to do that in response to in-world events. I don't think the fact that other players use inappropriate means is necessarily detrimental to my own experience in these cases, but they can plausibly be called inappropriate.
Changes to the way the world works are however, perfectly appropriate. Magic rules are highly arbitrary to begin with, and in D&D more so than usual. Why, for instance, can a warrior get multiple attacks per round just by leveling up but a spellcaster never gets multiple spells per round unless they have access to certain metamagics (of which I don't even now if they're canonical)? Does it make sense? Why does one class get two of its class-typical actions per round while another does not? Balance, people say, but that's also a gameplay convention. Must characters of similar level be similar in power? Well, if so, wizards are considerably less powerful in lower levels but considerably more powerful in higher levels, so that does not happen in the first place.
Then, why do I tend to play with standard rules in a single-player CRPG? Because if I don't, talking to others about my game experience is less meaningful. There is no reason for any standard rule to be with necessity the way it is, unless it's susceptible to reality checks and alternatives appear silly.
