Have to ask when were the complaints about Ast healing made? If before 5.05 yea they were undertuned compared to both sch and whm on healing and rDps but the 5.05 buffs sorted Ast's healing out.
If they are complaining about Noct Ast then yea Noct Ast is inferior to Diurnal Ast in every possible way, healing output/mp conservation/freedom to dps more all better on Diurnal and atm there are very few fights in the game where Noct shields are needed over Diurnal cd shields. People still enjoy Noct Ast due to the extra work or the shielding/preventive playstyle but most still understand it is inferior to Diurnal and needs working out (going on 6 years so I don't hold my breath anymore )
If it's about the card system then yea the card system is a hot topic always will be now (Thx SE no matter what you do now constant complaints will be a thing) due to them reworking it, taking away all the buff manipulation which helped Ast standout more, outright say not going to touch it(back in 5.05 no word since) due to those who like it now which opens up the can of worms that is the people who liked it before they changed it (very stupid move to say this), and generally having major controller issues at high end play.
If it's healer complaints in general then yea