Experienced Azir mains know the problems with Azir(from their perspective strength points) and know what needs to be fixed. Azir's problems are BOTH his mobility and range.
Ahri has insane mobility but low range. Ziggs has insane range but low mobility. Having the combination of those two is what made Azir insanely strong in the hands of experienced players who practiced him and used him to his full potential.
Azir's identity, when first created, is an emperor commanding soldiers to do his work. His identity however changed by time into that very high skill ceiling play maker who could do everything in the right hands.
His nerfs were because professional players could exploit him fully and thus he was perma picked/banned. However, average players were barely able to do fine with his old numbers and thus his winrates are very low. The rework is to curb down either his range(and thus preserve his identity as the high skill cap champion who still commands soldiers) or his mobility(and thus remove the majority of the skill required to play him).
As an Azir main I can guarantee you that removing his mobility will only kill his play making and he will be turned into another Ziggs, that's what the majority of Azir mains agree on. Sacrificing some of the range to preserve his skill cap and play making potential is a good deal.