It suggests the new direction the Nim is to be heading to (according to Araq's blog post), i.e. turning away from GC, it would more or less ruin things for the guy talking.
2017-12-06 22:51:52

I think the goal is to make the core types (seq, strings) non-dependent on the GC so that Nim is easier to use from other languages that also have their GC or to use in constrained environment (no heap, embedded devices, real-time/deterministic constraints).

As far as i know the GC will always be a (supported) option.

2017-12-07 12:30:28
@mratsim Well, it seemed to me the current idea is to push the GC aside so that Nim will become scope-based "by default" with optional GC just where it's needed. Thanks for the explanation though.
2017-12-08 17:46:09