I think it's important, for him to play just as he would if he was walking even if that developmental skill alludes us. It is important for him to get that exercise and to work climbing stairs and crawling over bridges. It is important for him to see that reward of hard work (climbing) being paired with fun (sliding). It is important for him to learn to move out of the way at the end of the slide. It is important for him to learn his limitations in the form of injuries, hopefully minor. It is important for him to get dirty as the sweat from sun and exertion meets dust from mulch and sand. It is important for him to have typical experiences within the realm of his physical limitations.
I think it is important for others to see too. Any other two and a half year old would be out there playing and toddling around, so Johnny is too. Would we let him scootch across the grocery store floor to prove a point that he can still have typical experiences? No. Is it appropriate for him to play with older kids, under supervision, even if he isn't walking? Yes. I think it was also important for people to see that he can do the stairs or the slide, with just a few extra moments of patience. Nobody had to wait long for him to either go or to move to a different part of the playground and if they had, I would have encouraged Johnny to keep moving just as I would have the girls. It is important for others to see that he has fun and delights in the same activities as anyone else.
I hope for continued growth and experiences with Johnny like this morning. I enjoy watching him grow and to make his own way in the world. We want to encourage that sameness when appropriate and to facilitate assistance when needed. We don't know when or how each experience will happen in his life, but we are thankful to be around for the journey.