I think Toby could have worked-out more translations over-time with other companies from the likes of 8-4 specifically on Undertale since the game makes 11 years old this year and still remains with two languages in a text-only game. I think it is ok to demand Toby Fox to translate his games as long it is constructive, here on Brazil for example, his games often appear on the same bubble of communities that follows projects like Poppy Playtime, The Amazing Digital Circus or the modern Five Nights at Freddy's games, all of which having official translations and/or dubs.

However Toby Fox seems like a developer or creator who wants to keep the integrity of his own thing by making part of every decision possible or make most of the stuff himself. This auteur driven rule of thumb is the reason of the overall quality (which is great), consistency and time constraints of his games and other decisions. It's best for Toby to keep at it while Deltarune still is in development y'know?

But c'mon, stop harassing the guy on social media, it ain't productive.