Yes and no. The tech doesn't matter but that is The Point. That is, your tech won't save bad product. Using the latest cool kids framework or buzzwordy tool won't save bad product.
Yes, the business you're in matters. No, it doesn't matter how you build them - as long as it's quickly. If you outgrow you're overly simplistic stack, that is a _great_ problem to have.
Arguably Pieter might be at this point already and he doesn’t care. With the right tech and more people he could scale some of his businesses further but he deliberately doesn’t want that as its diminished returns for him, personally.
Right on. With complexity also comes responsibility and commitment. Sometimes less is more. It might not be sexy. It might not win awards. But that can mean less stress and less risk.
Yes, the business you're in matters. No, it doesn't matter how you build them - as long as it's quickly. If you outgrow you're overly simplistic stack, that is a _great_ problem to have.