Seems like it's not built on top of LaTex, so you presumably can't drop into LaTex when Typst can't do what you need, or did I just miss that?

LaTex is positively arcane, but I still use it for all my writing since it's so incredibly versatile: Academic papers, letters, contracts, forms, invoices, tons of packages, pretty easy to apply regional standards, ...

How I manage to not go insane is Org Mode: I can write almost everything in something similar to Markdown but do inline LaTex as needed (since it compiles from Org to Latex to PDF). I find that incredibly powerful.