If you're doing it mostly for fun with a side benefit of recognizing a few characters here and there, go for it. Just know you're choosing to learn in a way that's not really recommended for most.
If your learning goals are mostly focused around reading, it's helpful a bit.
If you want to actually understand and use the language, hiragana, katakana, vocab and grammar have much higher utility.
My most complete advice would be to focus exclusively on the language you’re learning and don’t futz around with half-measures, but who am I to tell you what to study? If you’ve gotta satisfy the itch, then sure, you might learn something.
