Bell and Rogers are big companies with deep pockets. Koodo may be owned by Telus but it operates as a flanker with a smaller budget and catering to what the majority of its customers are demanding. I'm sure if there were a roar for Wifi calling, they'd have it.
And wind better offer wifi calling because their coverage is awful outside of their Zones.
Rogers gets to eat your cake and have it too. Read the terms and conditions. Some people might gripe that It's a new way for the telcos to charge for using your own pre-configured wifi connection which is traditionally a "free" perk. ;-)