You make a fair distinction in regards to general input-based value and labor based value.
You don't need to look far to find posters using this argument to rationalize the value of BTC. Many contend that BTC's proof of work is the only possibility for a truely secure ledger, that the masses of computing power invested create the value of BTC.
Also (as an aside irrelevant to my above question), I think you greatly overestimate the number of people who subscribe to a labour theory of value. Personally, I don't recall encountering people who subscribed to it other than far-left shitposters on twitter (who are definitely a minority, although a rather vocal one).