Hi!
As someone who also struggled a lot with interviews, I really feel for you as it sounds like you have put a huge amount of work into improving, which can make repeated interview rejections especially frustrating.
I'm also neurodivergent, and I do think it can play role in interviews, particularly with things like rambling, struggling to structure thoughts quickly under pressure, interrupting slightly when nervous (I've done this more times than I'd like to admit!), or finding it difficult to retrieve examples on the spot. Interviews can be such an artificial environment and they often reward concise and highly structured communication under time pressure, which does not always align naturally with how our brains process information.
One thing I would say though is the fact that you are getting interviews/ACs in the first place is a strong sign that firms already see potential in you. Therefore, it is likely more of a technique or presentation issue rather than a capability issue (although I appreciate that may not be super reassuring).
I also think it is definitely worth exploring accommodations rather than feeling like you have to force yourself through the "standard process". I totally understand being nervous about asking for accommodations, and it made me feel slightly uncomfortable last cycle, but graduate recruitment teams have always been super receptive and it is worth it to give yourself the best shot. Depending on the firm, adjustments like receiving written instructions, extra processing time, rest breaks, or flexibility in assessment formats can sometimes be available, so I'd definitely enquire with the firm about what they can offer.
In terms of practical things that helped me personally, I found it really useful to massively simplify my answer structures. I would almost force myself to start with a headline/signposting sentence like "There are two main reasons for that..." because otherwise I could end up going down too many tangents, and it would keep me on track. I also found that having a few very well-practised examples for the core competencies helped reduce the "mind going blank" feeling as I was not trying to think of something completely now on the spot.
You also mentioned that your diagnosis is recent, and I think that is important to keep in mind too. I found that there was a period of learning how your brain works best and which coping strategies genuinely help you, rather than just trying to mask everything.
You are clearly reflective and resilient, and I think that the fact you are reaching these later stages show that you are more than capable of securing an offer. I hope you are able to find what works best for you!
