Practically impossible for this developer? Maybe. Technically impossible? No.

We do have realtime GI solutions which don't require raytracing (voxel cone tracing, sdfgi, screenspace, etc). None of which require any 'special' hardware.

Raytracing is just simpler and doesn't need as much manual work to handle cases where traditional rasterisation might fail (eg; light leaking). But there's not many things it can do which we can't already achieve with rasterisation tricks.
Raytracing is mostly useful for developers who don't have the time/budget/skillset to get the same visual quality with traditional rasterisation.

However, in an industry which seems to prioritise getting things released as cheaply and quickly as possible, we're starting to see developers rely heavily on raytracing, and not allocating many resources into making their non-rt pipeline look nice.
Some are even starting to release games which require raytracing to work at all, because they completely cut the non-rt pipeline out of their budget.

So I'd argue that you're incorrect in theory, but very correct in practise (and getting even more correct with time).