"We knew they were going to completely gut the timeline to make it more convenient for film" isn't exactly a defense against the criticism that his appearance is out of left field, because it is. It's either a huge rewrite of the timeline or a huge rewrite of numenorean lifespan. I suppose it could also be them just telling multiple stories in tandem from different parts of the timeline, but that's bad story telling IMO and certainly enough evidence for saying he felt out of place and out of left-field.