Earth main is mediocre in the current meta. His main strong point is his shields, and shields are not that useful right now. Akatsuki Kakuzu is still pretty common and can just clear them, plus with stuff like irremovable ignition and poison, damage stacks up anyway. Right now, the only really decent thing in Earth main's skillset is the Attack reduction attackers suffer after his Deep Forest Wall mystery.

Cool...but, that attack stat drop doesn't even matter that much for ninjas who are more aligned towards ninjutsu damage, AKA most of the current meta: SOSP Naruto, Edo Madara and Final Battle Madara, Shisui Susanno'o and Shisui Kimono, Ashura, Gengetsu, combo Ginkaku and Kinkaku, Chinese style Sasuke, and AC Kakuzu all have a higher ninjutsu stat than attack stat. Other major ninjas (Obito Jinchuuriki, Madara Jinchuuriki, Pain Six Paths, Indra, NY Hashirama) have exactly balanced base atk and nin growth stats. The only currently meta ninja I can think of that would really suffer from Earth main's attack decease are Gate of Death Guy (and let's be real, you're gonna be blitzed before this matters), Zabuza Edo, and Itachi Chinese Style and Edo Itachi.

As things will be after this main skill update, I'd rank the mains like this in terms of their usefulness:

1) Fire main or water main (I personally think fire main has a ton of different utilities and I really value reflect. Being able to heal irremovable ignition and stay around thanks to dodge makes water main great too).

2) Wind main

3) Lightning main

4) Earth main

So yeah, based on this I really see no reason why Earth main's skills don't also deserve an update. I want a reason to play as a character other than fire main.