Seeing projects witch from condo to rental right now, during the design phase, a lot of the change has to do with amenity variety and competitiveness, at least for rentals. Here's what i'm noticing at work.
New (so usually aimed upmarket) rentals will need a grocery list of features to be competitive. Dog runs, Bike rooms, movie theatres, gyms, lounges, amenity kitchens, and rooftop patios are all common, and will sometimes be shoehorned into previously designed condo buildings, at the expense of smaller units. these are things the owner/developer will cover the (sometimes considerable) maintenance costs for via increased rents. TBH i don't really understand why a renter would pay inflated rents for this stuff, but i'm cheap lol. Theoretically, a rental building will also have more durable finishes in common areas, corridors, etc as the landlord has to pay upkeep on those. IE carpet tile in corridors instead of broadloom, tougher wall finishes in lobbies, etc. whether or not this plays out depends on the builder lol.
On the condo side, those same amenities, and their associated maintenance liabilities, are much less desireable. If you're buying a place, you probably care more about the unit itself, and are concerned about future condo fees/special assessments. A fancypants kitchen on the rooftop level with expensive cabinetry, getting banged up by all 200+ residents who have access to it because 'it's not theirs, so why take care of it' is not nearly as appealing to a savvy condo buyer as it would be to a renter, who isn't directly on the hook for upkeep.
The way things are now, at least, condo buildings are more unit-focused, with less amenities, and rentals are in an arms race with how many features they can cram in so the grocery list of 'free' amenities tenants can access looks more impressive.
Another kinda niche example of this is in Oliver, with it's stock of rentals turned condos. a lot of those buildings, particularly those built pre-energy crisis, in the 60's, have swimming pools in them. a lot of rental buildings will still have to pool up and running as an amenity. pretty much all of the condo buildings have their pools empty, to avoid maintenance and other liabilities. It was trip to see all those pools listed on Realtor.ca . They're actually really common, usually hidden in the basement or ground floor, facing the alley.
I would personally never buy a condo in a building with a pool due to maintenance costs. I almost feel the same way about underground parkades, except most people get more value from that, so the expense is more justified