iPhone 15 Plus:
I have Reduced Transparency, Reduce Motion, and Prefer Cross-Fade Transitions, all enabled. You have to have Liquid Glass set to Clear for Reduce Transparency.
I do use the Apple Podcasts app, but YouTube Music and DI.FM Radio apps for music.
I never see any rendering issues / glitches, and the UI is smooth & snappy.
iphone 17 pro:
0. none of the options you describe really disable LG and the glitches it introduced.
1. you don't need to switch LG to clear to reduce transparency. you can use reduce transparency with any LG theme. you just need to reenable "reduce transparency" after changing the theme. why? ask Tim.
2. in Podcasts you can tap between Home and Library to see the selection jank around the middle New tab. happens every time.
and if you tap to change episode sorting oldest to newest, then change it back, it 100% of the time won't ever change back again, unless you exit and enter the show again.
and semi daily when switching to it from lock screen the now playing layout will be garbled, either just the bottom card or the entire now playing screen is empty (at which point i usually restart the app).
and of course janky layout shifts and adjustments when switching between screens like search, show, episode, transcript, etc (which additionally also all involve sliding motion despite reduce motion + prefer fade on, but i will let that slide)
the list goes on