Yes, but I get the feeling you're looking down on that option. Because it's the easy way out.
No, not at all. Whatever works on a group by group basis (and player by player). I mean, 5E offers the three pillars, and every group emphasizes and incorporates them differently. While that's not the only way to frame this, the point is that there's no right way to do it - just the right way for the group. My group tends to emphasize exploration and combat, and roleplaying only as it serves the narrative and not as an end unto itself. Meaning, we don't go down the LARPing route and there's a limit to how much we, the players, inhabit our characters. We're a pretty casual group, though.
I mean "flaw" in the sense of "barrier to personal satisfaction in the game," which is particular to the player. It doesn't mean there's a design problem; it means there's a mismatch with the individual.
I'll get a little personal here. I work with a DM who absolutely loves doing the detailed worldbuilding thing. We've been playtesting a sci-fi setting he's written, where the species include various really alien options, like blobs and floating brains, and even the more humanesque cultures have very detailed cultures a la the Star Trek examples. I can tell he loves thinking up this stuff and that he's very proud of the diversity in his setting. And I do my best to make characters that will fit into those games--but I just can't ever seem to connect with them. It feels like too much space has already been filled in for me. The characters turn out lifeless and cardboard, and I don't enjoy playing them very much. They feel like all gimmick and no substance.
And I feel guilty as heck because the DM put in so much work, because I want to make characters that fit his world, and because in theory, I'm fully on board with the idea of limitations sparking creativity. It's not that I don't understand the principle or the appeal; it just doesn't lead to me creating characters that I consider to be successful. For me. For the DM himself, and players like him, it's probably glorious and stimulating.
I totally get that and wouldn't really enjoy playing a blob myself, at least not more than as a one-shot. I tend to play characters that I can relate to, even if they are very different from me. So no shardminds for me. I do like playing elves and try to be "elvish," but I also don't get too deep into thespianism, so there's a limit. But to address your previous point, if I merely want to play a "prettier human with pointy ears" and not get into the nonhuman elements of elvishness and what makes them different from humans, then I'll just play a human. If I'm going to play an elf, I do want to play something different.
I think also that your example illustrates the difference between worldbuilding as hobby/art in and of itself, worldbuiliding for storytelling, and worldbuilding for gaming. My worldbuilding for my novel(s) is very different and far more detailed than what I do for my game, which always has the game itself in mind. It is a complex topic, though, which I could write endlessly about, but don't want to go too far down the rabbit hole, not least because I don't want to be overly self-indulgent
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But it does sound like your DM might confuse this, and forget his players and the game itself in the process. It sounds like his worldbuilding would be better suited to story writing, or simply for the fun of worldbuilding (as a hobby/art form). Out of curiosity, has he ever asked if you are interested in playing these sorts of alien races?
