Disabled person and disability activist here-
If you aren't disabled yourself, please, please don't tell disabled people what we are and are not allowed to call ourselves.
"Identity as disabled" is wording created and fought for by actual disabled people. It has nothing at all to do with "identity politics" and nothing to do with gender ID.
First, no one can identify as disabled unless they have an actual medical condition or impairment. Period. "Identify as disabled" does not mean "I am able-bodied but I feel closely emotionally akin to disabled people on the inside." People without any knowledge or understanding of disability rights are projecting gender ID onto us disabled people without any thought or concern about us and without any willingness to actually listen to us.
There is not a disabled person alive who thinks "identify as disabled" includes able-bodied people who "feel disabled on the inside" or whatever. That simply is not what the term means.
The reason disabled people fought for the language of identity is two-fold.
First, it's to be inclusive of disabled, neurodiverse and chronically ill people who have struggled to get an actual medical diagnosis, as a way of telling people who are on waiting lists, or been fobbed off by doctors, that they are still considered valid and valued members of the disabled community even if they don't yet have a diagnosis from a doctor. This is mainly a problem that affects autistic adult women (getting an autism diagnosis as an adult is very hard and can take years, and women and girls really struggle to get diagnosed because women mask autism so much and it presents differently to boys). Second, women with chronic illnesses such as ME/CFS, fibromyalgia, and similar. There's a long history of women with chronic illness being fobbed off by doctors and told it's all in their head.
Traditionally disability politics have not always been welcoming to chronically ill people due to the SMoD and the politics behind it (which was explicitly spelled out in some of the early literature from SMoD), and there's been a push in recent years to say that chronic illness is a form of disability, and that people with chronic illness are welcome within the disabled community should they choose to ID as disabled.
The second reason is because lots of people with impairments choose not to ID as disabled, and actively reject the label of disabled, and reject the fact society pushes that label on them against their consent. This is especially an issue within the Deaf community and the autistic community. Lots of d/Deaf people do not consider deafness to be a disability but simply an alternate form of communication (since the SMoD holds that they are disabled by access barriers in abeist society) and plenty of autistic people think that being autistic is just having a brain that works differently and not a disability. Of course plenty of D/deaf and autistic people do consider themselves disabled - that's why "identify as disabled" is important, to give people a choice as to whether they consider their condition or impairment to be one that disables them or not.
Having said all that, the original point of the thread, that disabled people are often horrendously ignored by DEI work, is absolutely true and I thank the OP for starting a thread about it.