I upgraded my 27" 1440p LCD to a 27" 4k OLED (PG27UCDM) and for me text rendering was a big upgrade.

Yes there is color fringing if I take a zoomed in picture with my camera, but nothing I notice in day to day use. And I've been highly annoyed by missing or bad ClearType rendering.

I specifically went for the 27" to get the extra pixel density though. I might not have been happy with the 32" variant.

That said, the true blacks and bright whites is something else. For me a very significant upgrade both on the desktop and in games, despite the previous being an upper-level LCD when I bought it 4-5 years ago.