Don’t worry, triples will back soon
They won’t they really won’t. Neither will 26, elastomer forks and flex stems.
Thing is if you are going to have a front mech it costs nothing to add an extra chainring. Weight is negligible and it’s really useful.
38/26 – 38s not really good enough for road transitions or decent fire roads, 26 isn’t exactly alpine. 38 is quite big for a lot of single track (I wouldn’t race on 38) and 26 is pretty useless for that so you’re in no mans land a lot of the time.
42/32/24 – leave it in the 32 (the most popular 1x chain ring) for everything apart from road/fire road/descents or steep climbs. Think the granny on my XTR M980 weighs about a fart.