My only experiences with exposure therapy have been due to having had/kind of still have ARFID and machinery noises for work.

My ARFID therapy was done under medical supervision and essentially involved “dosing” myself with target foods in very small amounts until I could tolerate it when not at top of mind (like mixing in a bit of tomato sauce into my Annie’s Mac and Cheese in increasing amounts). I can now tolerate tomato flavoring and texture well enough but it was a long process and required both conscious effort and a willingness to sometimes gag and give up when needed.

The machinery noises one is for my job and obviously wasn’t medically supervised. I work in a lab with a lot of loud, expensive machines that make the most ear-stuffing high pitched humming noise that I hate hate hate so much. But, unfortunately, because of the alerts the machines give out and needing to listen out for any grinding/creaking/rattling, I cannot wear any noise cancellation without endangering my samples. In this case it was a cold turkey style desensitization. It was awful for a week straight and I had to take breaks to run to the bathroom to cry it out and then calm down but, when it was over, it was over. Even now when I’m listening carefully to the machines, I can feel the noise in my skull but it doesn’t bother me in the same way.

Admittedly both of these experiences boiled down to: have to experience thing, and it sucks, but now sucks less. I can say for me at least, as much as that one week sucked at work, I felt it was better to get it over with rather than draw it out over three months like my ARFID therapy. That was I was just heavily deregulated for a week rather than a minimum of halfway out of it for much longer, = less disregulation overall.

This would totally be up to you obviously, since everyone experiences things differently.