I think part of it is that - more so in original Zendikar, much less so in BFZ but still somewhat - it's
way harder to reasonably block landfall creatures that grow in toughness. And I don't even mean something like
Plated Geopede where it has first strike!
Blocking a
Steppe Lynx requires you to pay two mana and get a
Lumengrid Warden statline, and trading with it requires paying three mana for a 3/2 (totally fair baseline, but you're trading not one but
two mana down, which is disastrous tempo-wise even when they don't have a trick). The original landfall creatures got stupidly big. The subsequent ones were "only" a 3/3 for 2 attacking on turn 3,
Snapping Gnarlid still trading with a three-drop most of the time.
It's a mechanic that is innately way, way better on offense, and every individual point of toughness much more so than every point of power (but every point of power is still a huge knob, 2 is waaaay more than 1). Really, it's not the best mechanic to put on stuff if you don't want an aggressive format at all. But here we are, having decided it is going to be here, +1/+0 is the way to do it given that imo.
ONLY VAGUELY RELATED STORY: Back when WotC employees used to show up at random places and just play Magic against all comers, I got Dave Humpherys talking about
Goblin Guide, one of my favorite one drops. He said that originally, the drawback on the Guide was to put the land
into play... which did not last very long, since the Guide was "when you attack, ~40% chance you trigger all your opponent's landfall abilities and put your entire team directly into the graveyard"
. And that's just a really funny thought to me.