it depends on the willingness of the reader which can be completely unpredictable, basically some folks will and some folks wont. Like when I'm reading content sometimes if it's content that grabs me I will zoom to read but if it's something that I'm not interested in or it's still too blurry to read even after zooming I will not bother.
This is also something to consider if you're aiming to get featured on any platform (namely Tapas or Webtoons) because most likely the folks who are reviewing content are along with any other criteria are looking for readability especially since these are platforms geared pretty strongly towards mobile. So if your art/text is all pixels that's gonna be an immediate pass
It's also worth noting the size limitations where your uploading. As far as I know Webtoon limits you to 800px wide so if you go for B that's gonna be really tiny text, same for trying to squeeze it into Tapas' 940px limitation.
I've seen these kinds of comics on Tapas and if you've got poor formatting and it's hard to read you will 100% lose out on readers, subscribers and other kinds of engagements so do try to consider these things as you go forward.