I think that’s ridiculous the the bottom layer of the part infill should be compromised in any way to make raft separation easier.
I use 3rd party ABS and the peel ratio has to be set right down to 25 and the effect of that on the part then is the infill on the bottom is weak and often whole perimeter strings detached from the part when I remove the support roof.
This seems ridiculous that the solution to making the raft easier to remove is adjusting the infill and probably small changes in the support roof and raft.
What needs to be done is keep the raft a constant structure, and simply adjust the air gap between that and the part. Leave the part infill at 100% or 99% infill, and change the peel ratio such that it’s an air gap between the part and raft/support roof. This will make much better parts and potentially easier to remove as well as a bonus.