Companies could already outsource their development to Estonia or Ukraine (and done do) but there are many hidden costs to this.

You are really late to this party, this has been happening since the late 90s.

And then you would be committing the classic blunder. Putting more engineers on a late project makes it later.

As talented as the Ukrainian or Estonian engineers might be you're unlikely to see any real savings over time. Just scheduling things a full work day apart in time zones is really difficult. Effectively communicating is even more difficult. Then there's stupid little shit like one machine in a remote office set to a different locale than the main office that breaks things in stupid ways.

Engineering throughput definitely doesn't scale linearly with the size of the engineering team. Good on you for never having managed to have heard of Fred Brooks though.

They already do!! Still not enough engineers.