As of last month...not my experience.
So... tell us exactly what your experience was? Outside of some very specific cases, I have never seen that happen at WDW, and I have been visiting there literally since the first year the Park was open.
That doesn't mean that you and I will always have the exact same experience - I understand that. But *generally* speaking, as my friend
@Evita_W said above, there may have been a misunderstanding about how, where, and when you wait, and load as a mobility device user at WDW. Other factors can be the time of day, which bus stop you choose, and (literally) where you are - in the queue, as well as at WDW.
There are 2 basic queue types at WDW bus stops: a "mainstreamed" queue, where you go through the line with everyone else, and then pull out of the line at a designated exit point that is roughly where the back door to the bus is, and there are (last I checked) still a few queues that don't have the exit point, and you simply bypass the mainstream queue, and go directly to a marked location to wait your turn to board the bus.
There are some queues that can be confusing for mobility users, as they are not well marked at the entrance, and if a CM is not present to guide you to where you should enter the queue, and where to wait, I could see how a driver would actually not be able to load you.
- If you were (for example) in the "mainstream" queue line, even if the driver could clearly *see* you, they would not be able to load you until you were completely through that queue, and to the exit point - they aren't going to ask people who are in front of you in line to move so that you can be loaded before them; that is not how the system is set up.
- If you were (for example) at a bus stop for a Resort hotel that has multiple stops on a loop, then yes, this is a real possibility that the seats are already occupied when the bus arrives. This can be a real problem, especially at larger Resorts, and particularly during "rush hours" (usually morning/rope drop) when lots of people are trying to leave the Resort hotel to get to the Parks. (If that's the case, always ask for a room closest to the front desk; usually that's the first stop on the loop around the Resort, and often your best shot at consistently getting a spot on the bus)
It is my (personal) understanding that *if* someone is in those seats, then the driver is supposed to ask them to move if a
mobility device user is present, and read to load at the next stop. However, the Guests who are occupying those seats do not have to give them up if they have a mobility issue or hidden disability that requires that they sit during transit on the bus - in other words, those people may have every "right" to use those seats, we just can't see *why* They don't have to explain themselves, other than to say that they need to sit, just as you or I don't have to explain why we need to use a mobility device - we just do, and that's enough. Additionally, it is my understanding that if there are no other seats available when the driver opens the back door, the seated Guests (regardless of disability) do not have to move, because there is no similar accommodation for them available.
That's how it was explained to me - by a lovely WDW driver one evening when we were chatting. We had decided to skip fireworks, and when we got to our Resort bus, it was literally empty except for us! We had a very nice visit with the driver during our own "private bus" to our Resort that night! (Hat tip to Tim Tracker: I was "Queen of The Bus!" LOL)
And yes, there are some drivers who are not well-trained *or* well-mannered; coming back from the pandemic, it is my understanding that there are also many new drivers as well, who may not yet be accustomed to working with Guests who have mobility devices, many of whom are more knowledgeable about how the system *should* work than then driver!
So - what was your experience? Did it look like any of the scenarios above? I'm genuinely curious - I always want everyone here to have the best possible trip, and sometimes the difference between a trip, and an *AWESOME* trip is just knowing a few little "tweaks" to try next time!