Hard disagree. I work a lot with numbers, both hand-written and typed. I’ve yet to come across a situation where spaces are not sufficiently clear for readability. Using spaces for separation has never been an issue with letters, why would it be an issue with numbers?

I’ll be honest: It’s complete insanity to use commas within a number. If you need laughably high precision, use spaces for readability. If you need a lot of zeros, use power notation.

There is no excuse for putting commas in a number. I rest my case.