This topic drives me a little crazy.
Speaking strictly about bolt action rifles:
Suppressors can impact a rifles accuracy and precision regardless of load.
Why? Barrel harmonics change dramatically. In some very rare instances you might need a change in charge if you have any exceptionally high back pressure can.
Long, skinny, fluted barrel with a heavy steel can now hanging off the end? Yeah, you're going to see a huge POI shift and likely some degradation in groups.
Thick profile, short barrel with a titanium can on the end? You might notice no difference at all.
My 20" 300 PRC with a 9oz titanium can has absolutely no change in accuracy or precision between can or no can.
A change in load could solve the issue, but it's important to note the distinction in cause and effect here.