Funny how virtually zero successful startups have followed your model of paying people 100k+ at the beginning (first 1-2 years, pre-series A, or pre-profitability.) Probably just a coincidence though.
Let's say that I usually make $160k/year, and I'm willing to work for half that at a startup for four years, which means that I'm giving up $320k in income.
I'm not going to do that for a chance at earning $320k, but I'll definitely do so for a 10% chance at earning $3.2M. Which means that if the company exits four years later at $50MM, I'd need a 6.4% equity stake to make my target. If the company exits for any less than $5M, I've lost money.
Naturally, this is a simplified analysis of the situation, but it illustrates an important point. I know of a lot of startups that want to pay their employees peanuts, while at the same time giving them a tiny slice of the pie.
None of these companies have been massively successful either, in part due to the best talent having zero interest in committing to a company where they aren't valued.
Your reasoning is spot on but the numbers get even more unappealing once dilution in future rounds of financing kicks in.
If you have the experience, be a co-founder at a startup with pretty big upside. If you can't find that, the 150K/year salaries are a much better deal than <5% equities.