Apparently they're "completely optional"[1] but they chose to use them in all the examples ¯\_(ツ)_/¯

[1]: https://marcobambini.github.io/gravity/#/syntax

Calling it cancer is a bit hard. But I agree that semicolons are likely unnecessary.

I see no problem with semicolons. I guess it is mostly personal preferences.

Мышкин ;)