I think the origin point would have been better expressed with that nuance: if you have the budget, staff (design, dev, QA), and need to customize everything, rolling your own is probably best.

Frameworks are for the 99% of projects where not all of those are true. I’ve had good results limiting gratuitous changes that way: “do we want to pay to change this and test all of our supported browsers/accessibility/RTL?” is a lot better than “No”.