Because fediverse projects use open standards, anyone can develop software that interfaces with it. You can see this in the large number of different Lemmy apps that are now available.
Reddit was accessible because it was open to developers to create accessibility tools. We are now seeing issues because they've cut off API access.
Because the open standards are fundamental to fediverse projects, there is no CEO who can block access.
Someone is making access ability tools. If not, you can be the one who does.