I have read - don't know first hand - many times that this site is outdated and inaccurate. I don't use it for that reason.
Disney recommends 90 minutes travel time using their transportation for resort to resort transfers. In general, it doesn't take that much time. But it can and we allow that amount of time for dinner ADRs. Also, we budget for some (several) resort to resort taxis. Budgeted and saved for over time, it does not amount to a lot of money in the overall scheme of things.
In general,
Buses run about every 20 minutes. If you just miss your bus you can count on waiting a good 20 minutes. Sometimes more, most times less, but count on 20 minutes.
Same goes for the Friendship Boats that service the BC. It is much quicker, 5 - 7 minutes, to walk to Epcot. The boat dock is actually in the opposite direction toward the YC. I think the walk to Hollywood Studios is 15 - 20 minutes. I find it a pleasant walk, unless it is brutally hot, and we often walk, especially if we just missed the boat. You can often beat the next boat by walking.