It's generally a good idea to cast as wide a net as possible, within reason. There are a few big considerations like making sure that the terms of service are acceptable as well as managing the amount of time investment it takes to upload to a bunch of sites (for example, just uploading to Tapas and Webtoons doesn't take long, but hypothetically if you had like 10 different websites that you were posting to then getting them all updated might be a significant time investment).
Webtoons is pretty solid though and generally speaking has a larger audience than Tapas, so while you wont always perform better there (my first comic only got like... less than 70 subs over there over a year and almost 100 on Tapas in the same timeframe) it's not a bad idea to plop it there anyways. A number of people I've talked to about webcomics IRL have never heard of Tapas but are familiar with Webtoons so being able to point people to your comic where they already have an account is a big deal for accessibility.
