It can affect harmonics of the barrel otherwise your biggest worry would be uneven pressure. With any non-FF rail things like different sling pressure, bi-pod pressure in this case, etc can vary from shot to shot. Im not a math guy but even 1/16" of barrel movement will have a noticeable impact at range.
I understand that bipod versus no bipod will alter POI.
Here’s my thought – wouldn’t the bipod, assuming it hasn’t been moved (left on the same part of the handguard), consistently alter the POI?
What I’m saying is - if you keep the bipod on the rifle, would the altered POI be consistent enough that you could adjust your sights and compensate for it?
It’s not just the fact that the bi-pod is on the rail. It’s the pressure imparted to the barrel via the bi-pod and rail. Unlikely that the pressure will be equal from shot to shot.
Bi-pods are sometimes “loaded” by putting forward and downward pressure on the rifle. This varies from shot to shot. Sometimes bi-pods are not loaded, which of course means the pressure on the barrel would be different.
Try it and see if you can make the point of impact change. Take off the bi-pod and shoot the rifle from no rest (off hand), soft rest, and hard rest. Then add the bi-pod and try various scenarios.
If you can guarantee that you will always load the bipod with the same amount of pressure, then it might not shift the POI too much in any random direction. The experience I’ve had with them is that unless they are affixed in a way Not to affect the barrel then they’re more trouble than their worth.