I have some real world experience that might help you.

I used a modern-day KMC 8.93 8-speed chain with a 6 speed Ultra freewheel,13-24 cogs, Shimano 600 Arabesque derailleurs and Dura Ace 7400 8-speed crankset with 53/39 rings. Worked perfect. No chain rub, no derailleur locks, nothing. Just smooth shifting.

Recently swapped to a Velo Orange 48/34 compact crankset and 14-28 cogs on the same Ultra freewheel. Still no apparent chain issues but the derailleur does occasionally lock up when I slam it into biggest cog while on the biggest chainring. I suspect it may be a chain length issue (I did add a few links), a needed derailleur adjustment or a derailleur capacity limitation. I don’t think it’s the 8 speed chain contributing to this but I haven’t ruled it out. Still very ridable so I haven’t spent much time diagnosing the root cause.