I’m not sure if it’s unprofessional or not. I prefer email for professional things, but context matters a lot.
It’s not that I don’t text at all, I prefer text for social stuff among friends and family. Plus more immediate messaging like “where you at?” and “send me that 6-digit code you just got.” I prefer email for slower discussions and things that require me to think or research.
But say you meet someone semi-professionally and you exchange numbers. Later on they hit you with a text like “I run a business leaders meetup here in town and we’d love for you to speak at it, wanna do it?” That’s a professional ask and should probably be answered where it was asked. I’d argue it’s maybe a little unprofessional to be like “Could we move this to email?”
I do feel obliged to say: if your email is just such a mess and feels like a lost cause to you, that actually does make you unprofessional. It means you can’t be counted on to be communicated with, and that’s fully half of being professional. I suppose you can skip around the issue by texting, if that is a possiblity in some limited professional interaction, but that’s only going to be good for the occassional one-off. Maybe it’ll even make you seem amiable and hip for a minute. But your texting app certainly isn’t somehow a “better inbox”. Any communication issues you have will eventually follow you there.