author, too much focus on the social aspects when MC has shown himself to be a highly practical character and simply put the practical reasons for clothing should provide plenty of reason to wear more clothing. his body is new, no calluses or weathered skin to prevent all the constant little Knicks, cuts, scratches, bruises, and etc you get running around in the woods. you try going for a run through a forest in only a speedo and you will find out quite quickly a multitude of reasons to want to protect your body more. plus MC never had a body, so never felt physical pain nor discomfort, so beyond the whole struggle of walking/controlling body and feeling hunger MC Also should have been struggling with how sheer uncomfortable being unclothed in the woods and mountains can be and thus had the simple epiphany of the Practical reasons why humans wear clothes, and also had a desire to be wearing more of them. if for no other reason than to lessen constant need to channel spirit energy to heal all the little cuts and etc. plus the MC has a desire to limit how much he stands out and even without understanding the social "why" for wearing clothes should still be aware that Not doing so would make him stand out even more. in every other instance he is capable of reasoning things out from multiple directions, by having this issue get dragged out over multiple chapters you are compromising the integrity of the intelligence of the character you have created. there are many reasons for why the MC should be aware of the function and use of clothes, and you even state he is aware of them, but yet you continue to have him ignore all of it for a simple plot line "ignorant beast doesn't know to wear clothes" schtick. you could still have the same type conversation about the importance of clothes if you had him use raw hides of animals to garb himself. he could still ask those same questions about why they wear clothes in cities even if he, in the forest, is covering himself in hides for the practical reasons. he can still ask what is wrong with what he is wearing, as it does cover him, and why specific clothing is important if he is still covering himself.
I hate that his lifespan is so little even if he increases his cultivation it will only increase by 10 years! I also hope his little fiance remembers him and doesn't grow up to be a spoiled brat.
FFF