Similar problem on my M3P, end of year 2019/beginning year 2020 with the AMD Ryzen chip, but does have hardware radar. Super frustrating. It's been a problem on and off ever since I've owned the car, but it used to be easily fixed with a unpair repair of the phone. For the last 6 weeks or so, no luck after whatever update did this. I've now spent hours combing through 1400 contacts and removing symbols from first/middle/last names... including slashes, backslashes, @ symbols, dollars signs, underscores... but I'm leaving dashes, apostrophes, commas, and parentheses. I get the car, contacts load and look normal for about 30 seconds, then it goes back to "loading" and it never gets right again while I'm connected in the car. Basically the same thing it's been doing for weeks now. They have to fix this, it's unbearable. Next I'll see if any contact is a "vcard"... if Outlook could ever make this easier to tell in the modern versions of Outlook I'd love it. To go through all the symbols, I've been exporting to CSV, converting to Excel, then searching that way.
EDIT- I have Outlook 365, Exchange email at work, iphone 14 (about to be on version 17.2.1 here in a minute). A coworker has the same exact set up with an iphone 13, and his car works fine but it is an older intel chip M3.