You’re ignoring the fundamentals of economy by hand waving away all the other types of small businesses and only focusing on the most obvious targets to justify your argument. Construction, legal, retail, medical, mechanical, etc. all make a community even possible. And this benefit is a deduction, not a credit, so taxpayers aren’t directly paying anything for this benefit.
Look, I’m not disagreeing with you that everyone needs help. I completely agree. I’m also not going to defend all small businesses as being a good thing by default, because there are lots of shitty local places that pay and treat their staff awfully. But I think this is a simple win to allow average people to pursue their goals in business if they want to and make it just a little bit easier for them.
Fixing rent, grocery costs, healthcare, worker salaries, etc is far more complex than simply giving a tax deduction.