Pressure ranges stated on tyres tend to be fairly conservative both ways, but for off-road riding you want to start at the bottom end & tweak from there.
Too high pressure affects traction in all conditions, not just climbing; the tyres bounce off trail bumps rather than squishing around them, so handling is loose.
Too soft and they squirm and can burp or pinch-flat (even tubeless can pinch flat, the rim bead can cut the tyre sidewall).
Due to weight distribution on the bike, it's nearly always better to run lower pressure in the front than the rear.
All things considered, the exact pressures will be dependent on multiple factors, so there will be some experimenting required to find what's best for you, but everything else being equal, bigger tyre = lower pressure.