For our situation: my dad is on home-dialysis. He sees hospital staff 2-3 times a year only, and that too for no more than 10 minutes of specialist time and 20 minutes of nurse time. Apart from that, he is not at all occupying the healthcare facility. So, the impact on overall wait times is negligible.
For general scenario: I have been thru this process and I can assure you that officers are doing their job right. The process of getting an exemption for medical was insanely hard and they really checked there is no other reasonable way for my dad's life to go if he does not stay with me. You are not aware of this 4 year journey and the amount of points/documentation/proofs we had to provide. I can for sure say that the system is working and there is a barrier in place to protect canadians and tax-payers. However, if we look thru the same lense of "people abusing the system" then the H&C category should not exist. While I respect your opinion, we must keep this in mind that officers are also Canadians and they are always inclined to protect the people of Canada.