Despite my continuing interest in monitoring CB during cross-country trips, I can say it is certainly much more rare than it used to be - to get LEO reports, etc. Hit and miss east of the Mississippi with some comebacks and related chatter.
Waze now seems much more reliable and convenient.
On a certain backcountry interstate just north of the Florida state line last year, I tuned my HF rig onto Channel 19. Some truckers were giving instruction and even leading others on how to bypass the construction and interstate delays. We followed and it matched Waze perfectly.
Can't speak to Canada, but in the States with a correct CB setup, it can be useful. My CB doesn't sound like a 4 wheeler so I get plenty of feedback (Astatic D104 mic, slightest amount of echo, more then 4 watts). The fact that truckers can run 65 or higher in my States makes them not need it like they used to when it was 55. Some trucks are even setup to top out around 68 for safety and fuel mileage reasons.
Many 4x4 clubs require member to have a CB in their rig if they want to participate in club-organized trail rides, so when I had my Jeeps I had CBs. I left them on all the time, because why not, and I can't recall a single time they were useful on-road. Just my experience. Others may have had better luck.
Edit: pulled this from the unread topics list, didn't realize it was Canada when I responded. I only used my CBs in the USA so might be different up there.
I run a CB full time but it's more for entertainment or communication with friends/family. It's been completely forgotten as a countermeasure in western Canada. Seems like the 4x4 community is snapping more CBs lately. I haven't had the chance to hit the trails with my new radio and see how much chatter is on the gravel roads.
I usually keep mine on 19 but it is pretty quiet. Out on the prairies a guy can still have some range. I think if a group of people want cheap, close range comm's it's still an option. Each to there own. I still get the odd guy reply when I get on the air.
Most truck drivers in my area are using CBs. But that stay on phone most of time plugged in and talking to keep everyone updated. I just realized this is Canada forum. So guess letting everybody know way it is down south.