The only restriction that I know of for crown land is that you are not able to camp on the land. However all other social distancing rules apply. ex... no more then 5 in a group, stay 2m away and so on.
Best to check out Ontario website and read up on the rules and go from there.
https://covid-19.ontario.ca/.
Both Gov and heath leaders are asking for everyone to avoid unnecessary travel. Is good mental health necessary? I don't know but that will be up to you to decide. Also keep in mind if something happens to you and you end up in the hospital you'll be using resources that are already in high demand. again up to you if the risk is worth it.
As for BMA putting on a ride, I'm not sure if they can or will. The logistics of running one with social distancing rules would be a nightmare. We'll have to wait and see.