This is a terrible overview. The actual primary benefit of toasts is that they provide feedback on low-importance events without requiring the user to interact with them and without permanently taking up UI space. The web application I use most frequently would be infuriating if I had to deal with a modal window every time a toast would have been used, and UI space is at a premium for useful functionality, so occupying a permanent spot to relay those messages isn't a good solution either.

I wish software developers could drop this dogmatism. Same as the old Goto considered harmful trope outliving its usefulness and all that. It's always black and white - "people can misuse this tool, so this tool is inherently bad and should be eliminated from usage completely" - rather than acknowledging that many tools have great use cases even if they can also be abused.

There are many alternatives, OP lists some (banners, modals), but also inline messages, button states, next steps screens - not just modals.

There are also a lot of professional guis (think medical software), that use no toasts.