I think the problem is the argument:
"The Church allows it, therefore its is good i.e. it should be done".
Like using 4 EMHCs with a congregation of 60.
Like using altar girls, so then boys don’t want to serve.
Like singing folksy, poppy, simple hymns, so then people can’t/don’t want to stretch to chant.
Things like this are allowed, but are they good for the Church? Vat. II has been used to insert people’s personal preferences into our worship. It reminds me of what the music industry does: water it down and sugar it up = hit record. Except we deal in Truth rather than sentiment.
I think top of the current wish-list for liberal Catholics would be married priests. Why? Because of the delightful novelty. You would also be bringing the office down a peg: “He’s married, just like me!” This would continue the de-mystification process, started, ooooh, when the Bible began to be read like a historical document.
Except it’s not clever intellectual ideas that bring the crowds: it’s genuine holiness or false mysticism e.g. saint’s relics, true or false revelations, a priest or religious who can truly heal or bless. A priest who has a whiff of Heaven about him.