for every small business that "gets by", there are 2 (probably more) that go out of business due to not having grown sufficiently by the time they face some competition.
I think the idea that companies go under because they aren't ambitious enough says more about modern attitudes towards growth than it does about the reality of business.
A larger profitable company has more chance of survival by shrinking into a smaller profitable company. It's a buffer. But an already small profitable company doesn't have that option, there's more risk.
If your goal is to fight a monopoly, then the mere existence of competition means that you've accomplished your goal.