That used to be true. Speaking strictly constitutionally “invisible” is still a bit of an overstatement but not unfair. Regardless modern US VPs have some standardized additional roles (National Security Council member being the biggest one) and others assigned per administration which can and reportedly have impacted the administrations they’re party to.
I’m not sure I take your point about Harris’ invisibility in particular. She’s set a new record in her capacity as President of the Senate by casting the most tie-breaker votes in US history. On the flip side she’s drawn a lot of flak while working on the Central America Forward initiative (justified or not is a separate discussion). Her perceived invisibility isn’t because she hasn’t been getting publicly visible work done.
A speaker’s public record provides context for their current commentary. Trump’s tells us he is a bigot. Specifically a white supremacist. His recent rhetoric leans in to this. When pressed to clarify, justify, or recant these statements he either deflects or doubles down.
There is no reason to think he is suddenly well intentioned, operating in good faith, or otherwise deserving of some deference of judgement.