For me, I've managed to get around the same amount of followers for both (but I gained webtoon followers a lot faster.) I've found that if you're promoting your comic elsewhere, people are way more likely to look for your comic on webtoon since it's a more popular site.
I've also found that posting on tapas multiple times a week helps you in terms of algorithm and popularity. Tapas readers seem to be alright with shorter updates (there are a lot of comics that upload a page per update multiple times a week and seem to be doing great on tapas) Meanwhile, on webtoon, readers expect longer updates once per week, so that works on that site.
If you're in one of the less saturated genres (I'm in horror, which has way less featured series) you have more of a chance of being on the popular page and having people find you. However, if you're main genre Romance, Comedy, Fantasy or Action, you're going to have a hard time competing with the featured series and all the other comics on there.
I'm not sure if scroll or page format is preferred on tapas, but I see a whole lot more page comics on here than scroll (or at least the ones I'm reading)
I think the issue with tapas is that even the 'fresh' section, which is similar to webtoon's 'sort by date' section is that it still sorts fresh based on popularity (that's what I've heard, don't quote me on that)