I think the most charitable way to respond is to empathize with the person who has spent >=$X monthly for the last N years and did not had contribute that amount to a mortgage instead as an available option. It's easy to respond to your opponent by assuming that all the unbound variables are on your side. What if they aren't?
Don't get me wrong - I can empathise with how hard it can be to get your own house or flat these days.
But I do not think OP's comment was fair to the landlords. It is not their fault that building materials are getting ridiculously expensive, that more and more people need to live in/near the cities to get a decent job and other factors that make owning your property less and less accessible.
