I think it's a common psychological phenomenon to always lag behind in accepting the current need for adapting to declining ability. I witnessed this with both my mother (multiple myeloma) and Annie (ALS). I think most of us would be the same. We hope that an "incident" was the result of factors not entirely related to the illness. So our physiological need to maintain as much normalcy as possible convinces us that we "won't let it happen again" - "we'll be more careful in the future".
In my experience it was better to let them come to accept the need for adaptation on their own - it actually didn't take too long. External pressure doesn't help them accept reality. Yes, they may get hurt, and an accident on their part can be very inconvenient for the CALS who have to deal with the consequences - to pick up the pieces. But, in my opinion, it is just part of what a CALS has to bear for the emotional and psychological well-being of our PALS. Offering them suggestions of what you think is needed is important, but letting them decide, knowing that they have your support, will also maintain the bond between CALS and PALS, which is especially important when they are spouses.
Just my own humbly offered thoughts from my own experiences.