Ask HN: Why don't more OSS companies adopt licenses that exclude big companies?

I see a lot of complaining about big companies just taking OSS software and not contributing back. Why don't more companies just adopt a new license that excludes big companies from using their software in certain ways? For example: if you had 100+ million users before January 1, 2025, your company and its subsidiaries are not allowed to use or distribute this software for commercial purposes. This would level the playing field and give the small guys an advantage over big companies, lowering the barrier to entry and increasing competition. This is a net benefit for the world, no?