I think the major problem stems from the exponential power increase between levels.
in the past, the differences between a gear piece from a x.1 raid and a pieces from a x.3 raid were large enough to certainly be noticeable, but not large enough that measures needed to be taken to stop the game from becoming laughably easy.
However, with each expansion the same exponential growth occurred, with the power gap between levels growing wider, and so gear similarly needed to grow exponentially more powerful compared to weaker pieces. By time it reached Legion it got to the point where 7.3 gear could near-enough one-shot open world content, which was never the case with, say, ICC gear during Wrath. This is when they first started scaling (in Argus, at least) because the alternative is to make it too difficult for anyone without 7.3 gear. Once BFA came along, the exponential growth touched even the differences between levelling gear and M+ 15 gear. That’s why they introduced the scaling throughout the entire expansion.
Really what they would need to do is to re-balance the power chart so that each patch you’re looking at consistent power increases (i.e +100 primary stat per tier), though I can see that they would then have to get creative to keep raids balanced in a way that x.3 raids are thoroughly more difficult than x.1 raids without exponential increases in player power.