Many software engineers do. Considering how much value they create with their work, they are massively underpaid.
You could ask why? I'd argue it's anchoring to the magical 150k. For some reason SEs think that's peak engineering pay. It's not, and if you're doing meaningful work that adds top tier value you should be paid a lot more, or at a minimum given equity.
I hear this a lot, but what is your reference point that allow you to conclude that the engineers are underpaid. Do you use a percentage of profit generated from your contribution? (would you also pay the company for products that made a loss?)
Really, how is this measured?
An employer might make a million pounds from your work but if the going rate for the skills they need is £50K then that is what they will pay.
Nothing preventing them from starting their own business if they believe they can earn much more.
Sadly, not everything rolls neatly into a startup.