Those market studies are worthless because consumers don't know what is actually going on. They don't know what data is collected, where it's used, and they can't opt out.
Obviously if you lie to consumers you can get them to 'prefer' your product.
Not sure about market studies, but I don't think the data is going to be very encouraging for this case either. E.g. in early 2024 Amazon introduced ads in Prime Video, which people were already paying for. I couldn't find more recent data, but from this source at least it seems growth hasn't stalled much: https://www.businessofapps.com/data/amazon-prime-video-stati...
This is not a clear cut example because Prime comes with a lot of other benefits which is a confounding factor. Might be worth looking at cable TV subscription numbers after they introduced ads, but I couldn't find any data with a quick search.
People confuse "ad-subsidized" with "I pay and still see ads". They're not the same thing.
And market studies show that people overwhelmingly prefer ads over payments.