I definitely view it as a red flag if a business doesn't have a website in 2026. It doesn't need to be a fancy website, but does at least need a list of products, business hours, work samples, and contact info. If they don't have that, then I view it as an indication that other aspects of their business might also be lacking in professionality or high friction.

That being said, if they have a strong presence on Google Maps with plenty of positive reviews, photos, menus, hours, etc., then that's usually good enough for me. At least the info on Google Maps is publicly visible without logging in, and reasonably well organized. But even then, I do often find myself looking for the "Website" link on Google Maps and feeling frustrated when there isn't one.

Relying solely on Facebook or Instagram feels a bit to me like having an @aol.com email address back in the day.

I haven't built a basic website in years, so I'm a bit out of the loop, but I would probably go with Google Sites if I wanted to set up a simple business page. It's got a WYSIWYG editor, it's free, it has support for custom domains, and presumably it will play nicely with Google SEO.