I can't disagree with this, but it rubs me the wrong way. The characters live in the world, but there's only so much bandwidth through the DM about it. I don't want to specify that I put on my shoes in the morning, I expect that to be the default.
I understand the complaint, but that's why I began with listing what I think reasonable implied defaults. D&D doesn't have hit locations, so it has to be assumed that if the PCs are wearing armor, then they are wearing armor that relatively equally protects their body - including for example gloves, helmets, and boots. But, conversely, since normal clothing doesn't provide any particular protection to their body, there is no reason to assume that normal clothing provides any particular protection to any part of the body.
Likewise, in most versions of D&D armor provides certain penalties to skill usage whereas normal clothing does not. It's reasonable to assume that something like wearing gloves would make certain tasks more difficult - ask anyone that has had to wear gloves. Any glove that offered no penalty at all on tasks would either have to be of such extraordinary quality that it should be listed on the character sheet and listed as worn ("masterwork surgeon's gloves (worn)" or some such), or else it can be assumed that it's of insufficient protective capacity to provide any meaningful protection against a contact poison or anything else for that matter.
What you very much want to avoid is fiction that is malleable to whatever would be useful at the moment. Trying to retcon the blank spaces in the fiction is a very rules lawyer-y sort of thing to do.
That said, in practice this would very much depend on the trust that a player has built up with me to that point. If this was the sort of player who had frequently in the past made negative calls of his own initiative reminding me of things that a munchkin would rather say silent about in hopes I'll forget them, I'm going to be much more lenient with them making reasonable but convenient positive call outs about the fiction. If they are the sort of players that seems to have 5 different utility arms for holding all the things that it would be convenient to hold - weapon, missile weapon, shield, light source, 10' pole, and a free hand to grab falling colleagues - and who always stays silent about fictional positioning that would negatively impact them, then I'm not going to have the slightest mercy here.
And even if they do convince me that a traveller's outfit has lightweight gloves because they are the sort of player that I do feel is scrupulously fair, it's probably going to knitted wool gloves and I'm just going to give them a circumstantial saving throw bonus and remember that the next time they want to do something that depends on sense of touch or fine motor skill those yarn gloves are going to apply a similar circumstance penalty.