The needed stack size is hard to determine by the compiler. It will try,
but will fail in many common cases. Therefore, the runtime will pick a
fixed stack size.
There is a tradeoff between avoiding stack overflows and wasting RAM.
This tradeoff depends on the application: some don't need large stack
sizes but do need a lot of memory, while others need deep stacks but
aren't so memory constrained. That's why I've added a flag to do this on
the command line: https://github.com/tinygo-org/tinygo/pull/3159
It may be reasonable to use a different stack size per chip, for example
chips with lots of RAM could default to a larger stack size. But I don't
think it's a good idea to do this per board.
