Having more small businesses is how you get less corporations and a healthier middle class
Except when the corporations just buy the small business. This is the big problem with breaking into an industry. If you do find a way to break in, then one of the larger guys will just buy you out or force you out. Facebook bought Insta for the sole reason to reduce competition. Meta bought them out at $1B, which was huge for a small business buyout. Post-Meta, Insta is now estimated to be worth $100B Literally a penny on the dollar for the buyout. Meta also bought out WhatsApp at $19B, currently estimated to be $109B worth today. Like things that are regular names at this point were once small businesses that were serious threats to larger companies. Meta's Messenger was under serious threat by WhatsApp prior to the buy out.
And sometimes the point is to just get rid of the business altogether. Microsoft bought out Wunderlist for the sole reason to kill off the app. Google bought out Waze and has constantly been keeping them just functioning, but in 2020 the FTC launched yet another investigation into Google over Waze.
Small businesses won't thrive without restricting some of the anti-competitive behavior of the larger corporations.