For sure - many of YRT's services are so infrequent they're basically useless. Off peak and weekend service is especially terrible.
I had to ride the 84 Oak Ridges route daily last summer and summer 2018 for a few weeks, and it really sucked. On the YRT map, YRT claimed the 84 was a regular service route, but iirc the route didn't run for about 3 hours in midday on weekdays and stopped running at something like 6:30 pm ish. I would've missed the last bus several times if the driver hadn't waited for me before leaving my stop. That driver was definitely one of the nicest I've ever met.
The route was a single bus running in a one-way loop around Oak Ridges, meaning I would have to make a pretty long detour when travelling in one direction, and the headway was just the time it took to drive around the circle - about 30ish mins (which I admit isn't the worst, but there definitely are YRT routes that are worse). One time my Viva Blue bus got delayed and I missed the connection, and I ended up having to walk down a stretch of Yonge with no sidewalk for something like 20 mins in 30+ degree weather.
Definitely a poor transit experience, even if the bus driver was extremely nice.