First of all, everyone has the right to complain even if they are not in the program, as long as it's legal.
Sercondly, Are you kidding me? Sounds like you haven't gone through the program and randomly commenting S word about things here which makes me a bit frustrated. The 15 - 19 months process time is meant to be the entire process time and this time hasn't been changed from before the pendamic. They don't even brother to change it at all at the moment. If I waited more than 19 months on just receiving the AOR (or not even an AOR, a denial because of missing documents) instead of getting the the application completed, I will be mad.
Again, don't ask people to be patient, they ain't you that don't care. Some of them their nomination are going to expired and so their work permit. They are now in an awkward situation. They can't extend their work permit. If you are them, how could you be patient and watching yourself slowly losing the job and becoming a illegal citizen? Don't pertenting a "good person", you ain't helping. What you said makes me feel like you lack of sympathy and just don't care and ask people to just wait to lose their job, their citizenship.
I don't see any benefit to be patient . Instead, we should find out a way to speed up their process by I.E submitting an online form to them for review whenever someone feels necessary, submitting feedback (suggestion, complain) to IRCC, etc. Or find out a way to get around it like I would suggest people to try EE if they are eligible. If you don't have a good way, just don't comment. At least, don't comment something is totally wrong.