We already have rune tag which can describe a single, Runic character. post #5968401 shows the artist name written in Runic text. post #5118265 shows a single identifiable Germanic Runic letter "Dagaz"
The singular rune tag only has 21 posts; runes has 1243. If anything we should get rid the redundant little one, I doubt there's anyone actually trying to find individual runic characters. And runes are frequently stylistic, not real text (ex: post #5411667), so adding "text" to the name doesn't improve anything either.
The issue is that there are about 180 posts tagged as runes just because of Nanashi Mumeis rune-shaped hairclip, and I would certainly not call it "text".
I also agree that most of the time runes are used merely as a stylistic choice rather than actual text, and tagging what is essentially just random gibberish as "text" is quite the stretch, and even if we split the tag into just runes and runic text, I doubt many people would be able to tell the difference, so chances are that runic text would end up probably just as a undertagged tag with a lot of mistags.
Speaking of that, fake text and faux text both exist, and fake text has a bunch of fake/faux runes in it. I don't even know if we need the distinction.