Whoever told you Tool sounded like Led Zeppelin should be slapped. There's influence there but they don't really share sonic DNA. Go listen to Gretta Van Fleet if you want a subpar clone of Zep.

I think Prog Rock as you know and expect it is almost entirely dead. Unless you're willing to venture into the realm of Progressive Metal (Opeth, Dream Theater, Mastodon, Porcupine Tree & Steven Wilson, Tool, Neurosis) then there isn't much to offer at this point. I'd sooner recommend you start listening to 90s Death Metal.

In the realm of emotional singers, there's plenty to offer. Weyes Blood had a lush album in 2019 called Titanic Rising that has a lot of resonance with 70s singer/songwriters. Lianne La Havas' self-titled album from 2020 was very good. Laura Marling has put out many good albums, and the most recent two are among the best. See if those bare any fruit