HW 2.5 is not just a CPU/GPU change (an easy upgrade for HW 2.0), nor is it a generational shift (e.g. HW 3.0 with twice the sensors or something), which suggests to me HW 2.5 is actually plugging holes in HW 2.0 with redundant wiring, new radar, new chips and power elements here and there.
I.e. HW 2.5 is probably the worst kind of vote of no-confidence in HW 2.0 given how soon it appeared. HW 2.5 seems like Tesla covering their behind. But will it be enough?
HW 2.5 seems like P90DL V3 to HW 2.0's P90DL V1.
This is just your assumption.
So far, AP2.0 is more or less at parity with AP1.0, despite a huge difference in the hardware.
Let's not judge until we are able to test HW2.0 FSD cars against HW2.5 FSD cars under identical conditions.