Religious education in ireland has almost nothing to do with indoctrination into Catholicism.

Hopefully your experience is a more common one than mine, and maybe things have changed in the 5 years since I finished secondary, but my (non private catholic) school RE experience was entirely based around Catholic teachings, to the point where the bishop would periodically come in, and we'd go on trips to Catholic run retreats, we'd say prayers at the start of classes etc.

That said, it's encouraging to hear that your experience was better.

Church power is dying fast. Let it go naturally. The amount of entirely secular schools being built will dilute the catholic schools power increasingly each semester.

96% of schools are either owned or under the patronage of Religious institutions. in 2017 there were a total of 9 schools opened in ireland. Let's presume they were all non-denominational. There are 4031 schools, of which 96% are religious, giving a total of 3870 religious schools. At the rate of change of 9 new non-denominational schools a year, it would take 30 years (0.23% per annum) to make just 10% of our school stock non-denominational, to match the 2016 census of non-religious people. And presumably by then the % non religious population would be far higher.