current Goku vs. Jiren

This is current Goku from the Manga vs. limit-breaker Jiren from the TOP.

Round 1- SSB Goku
Round 2- UI [sign] Goku

Goku in both, imo.

Really?

You think the scaling is that crazy now?

It depends if post-Merus training Goku became strong enough to close the gap limit in power that exists between MUI and UI Omen.
And this gap is massive. However, Goku himself is much more powerful than he was at the end of the ToP.

I'd say Round 1 to Jiren and Round 2 to Goku.