I must respectfully disagree, I see no reason to keep below 50mm.
This is very true, you dont have to. I do know some people who shoot street with zooms and they get some pretty good shots, but traditionally, street photography is about being close, being part of the scene so to speak and not a mile away.
But there isn’t a rule book, if you shoot street and use zoom and get shots you like (which is the most important thing), then by all means continue…
I agree with you Alan, I use a 28mm to 90mm usually set at 50mm and I also use a prime 50mm and 85mm but I find the primes are the best because they’re faster which really helps things.