Not to denigrate the content of the article or Linear - because it's a fantastic tool - but easy talking about profitability when you're able to spend a year in private beta, focusing on product. This is like talking about creating your own wealth, but not mentioning you have a trust fund.
You don't need a trust fund to keep a small team eating ramen for a year. Lots of people start businesses with just their savings and maybe a small loan.
Maybe that's not the kind of company you'd like to build, but if it's the only option given your financial circumstances, ramen it will be.
Is that what Linear did?
Linear founders had "savings" from previous exits. Some of the early ones really were ramen-scale from what I can tell.
So that's one way to come up with the capital you need. Start something, grow it, sell it for $$, and invest that $$ in a new company that you hope will be worth $$$$. Rinse and repeat. You don't have to make it big on your first try!
A $4.2 million seed round from Sequoia also didn't hurt. Maybe they were able to eat pizza instead of ramen because of that.