From my own personal experience this is extremely true. A while back I made myself a custom keyboard [0] which can enter lots of characters, mostly for linguistic tasks. I didn’t intend to start using it for things outside linguistics, but before long I was using it everywhere — and my inventory of available characters expanded correspondingly. I started to use curvy quotes and em/en-dashes in all my writings (even in this post!), and — more topically — I started using Unicode symbols in my programming, when possible. I don’t use them too much, mostly because there’s little need for them, but in scientific tasks it’s really useful to be able to type e.g. ‘λ’ instead of ‘wavelength’. I predict that as Unicode symbols become easier to input, programming languages will indeed start to utilise them more — the limiting factor is keyboard layout. (Indeed we can already see the start of this process in Julia, Raku and Haskell.)