I believe they are also eligible for a similar card? As long as your parent or spouse are of Indian Origin (don't even have to be Citizens), you should have the ability to get that card?

I was reading up a bit and I think it's a mix of what you said and people who would be eligible for the OCI Forever-visa but never bothered getting it. I imagine many Indian-Canadians never visit India outside of a special occasion, and with the pandemic being over there's a uptick of these occasions.