How does a programming language prevent the vast majority of bugs? I feel like we would all be using that language!

See Rust with Use-after-Free, fearless concurrency, etc.

My language is a step ahead of Rust, but not as strict as Ada, while being easier to read than Swift (especially where concurrency is involved).

I agree with your questioning of it being capable of preventing bugs, but your second point is quite likely false -- we have developed a bunch of very useful abstractions in "research" languages 50 years ago, only to re-discover them today (no null, algebraic data types, pattern matching, etc).