Some interesting takes there, but I think the update at the end highlights some important points:

Are a lot of the web­fonts we see to­day cruddy free fonts? Yes. And are many of those from Google Fonts? Also yes. But as a type de­signer, I would much rather have peo­ple us­ing cruddy free fonts than sys­tem fonts. Why? Be­cause it re­quires them to over­come their rest­ing in­er­tia—“why should I use web­fonts when I’ve got Geor­gia?” That first step is a big one. Even­tu­ally, some of these peo­ple will get sick of their cruddy web­fonts, and then they’ll be in the mar­ket for bet­ter ones. Which they won’t find at Google Fonts.

This is something I've definitely noticed, and the designers I work with are definitely at the point now where they are seeking out high quality paid webfonts. It's been a slow process whereas before it would be default system fonts; then it progressed to Google Fonts.

Google did a great job of making a huge library of fonts easily accessible to anyone who knows a small amount of html & css.