Nonsense, unless you think picking girl a,b or c is the only meaningful choices a game can have.
Of course it is. It is a game about romance and sex. Choices can be: 1) Who you romance. 2) In what way. 3) Whether you stay loyal or cheat. 4) Whether you stay together or brake-up and get with someone else. etc. Harem is just - I date everyone. And that is it.
Personally second time playing I skip through and I am not immersed at all. Kinda hard to stay involved with the story on the 5th time through just to see 3 scene's you missed. It just becomes a ctrl-fest as who wants too read 90% of the same scenes again and again. Very rarely does a separate girl's path change the game enough to read it all, no-one has the resources or time for it to be different enough to actually read again.
Why are you playing through a second time? The point of games with choices is to have a unique playthrough. I played through Baldur's gate 3 once. I've seen probably like 20% of that game, and that is ok, that was my unique playthrough and I enjoyed it, I don't need to play it again. If I want to see what other people have been up to in their playthrough I can go on youtube. You want to see other fap scenes download the open gallery mod. It is very weird to me that you want to see everything in a choice game all at the same time. If you feel like you are missing out on the story then that means it won't be just a ctrl-fest, because the story will be very different, but if the story is 90% the same and you feel like you are missing out just on the fap, then just open the gallery.
Again both types of vn can have meaningful choices I have no idea how you think that is not the case and keep a straight face while saying it. If the vn has any type of decent story it can have meaningful choices harem or not does not change this.
It is not the focus, and should not be the focus in a game about romance and sex. I don't come to romantic VN's to decide whether I am going to fight for the rebels or the empire, it CAN be an extra part of the game but only if the romance is very well fleshed out first and foremost.