He had a stopover in Middle Earth to play a fifty year old person who is half the size of a regular person, so he's kinda like a child, but kinda not, because although fifty is middle-aged to us, it's still pretty young for a Hobbit.
So...an oddball character stealthing as a child.
I've noticed it, too.
He went from a popular child actor--a kind of leading young man in family films--to LOTR, one of the biggest blockbusting trilogies of all time, and then . . . kind of just like a bunch of weird shit. He doesn't seem to take a lot of normal roles in standard films. He's not going to show up in the next Jurassic Park movie or appear as a lawyer in a 1950s period piece or whatever.
https://movieweb.com/the-toxic-avenger-elijah-wood-villain/?fbclid=IwAR1QHljMqXZx3b9Fsnsa4TMcAQKKo13L4aeO6D1SjTwq-rCbe2lRpjSPPCs
The Toxic Avenger Reboot Lands Elijah Wood as the Main Villain
I saw something about that the other day. Just further proof of the OP's point.
I wonder if Wood actively seeks out off-beat roles or if they find him.