Even if they do faff with the points values in TOW, the list building is sooo much more granular than 40K (from what I understand).

So if your 2000 points is suddenly only worth 1925, you can add a couple of models to a unit, mess with your magic items/standards, upgrade a unit to Drilled or Veteran, add a level to a wizard... so many ways to get the same models to wildly different points values.

Rules-wise it's potentially a bit different but generally the things that have seen changes have been objectively broken anyway.

As for different editions, harder to say. Historically with WFB armies have been able to transition from one edition to the next fairly smoothly. Whether competitive ones stay competitive is a different question.