I don’t think these things are lookalike contests. He doesn't have the (chin?) for Nimoy, not Spock. Daniel Craig doesn’t looks like Sean Conney, either! And the less we say about Batman....Peck acted well. But... he should have kept the beard. He doesn't have the chin for Spock.
One thing I've learned about Trek fandom is that, given the benefit of hindsight, history has been a lot kinder to Star Trek Voyager in general and Janeway in specific.Janeway used to never be one my radar, I disliked her during Voyager's initial run. But a relatively recent rewatch has made me come around on her.