Hi Suealpha
welcome to the Apple (user-to-user) Community!
Re: Can my MacBook Pro be paired by Bluetooth with my hearing aids?
Am no expert in this area, yet your question surely deserves some response.
It seems your audiologists may be right, technically, about pairing not being possible.
Seems the Signia Stretta Stretta Aya M is not in the list of Hearing Aids that use bidirectional streaming, so they may not be compatibile with the Mac.
List of Made for iPhone hearing devices - Apple Support (bi-directional streaming is marked *)
_____________________________
Yet a MacBook Pro introduced in 2021 or later with macOS Sonoma 14 or later is compatible with some "Made for iPhone" (MFi) Hearing (those marked * that use bidirectional streaming).
If you want to check which MacBook Pro model (year) you are using:
try Apple menu > "About this Mac"
____________________________________
More info: Apple Support's online articles:
Re: compatibility: "Made for iPhone hearing devices can be paired only with selected Mac computers with the M1 chip, and all Mac computers with the M2 or M3 chip".
_________
Re: pairing: If your hearing devices are already paired to another nearby device, such as an iPhone or iPad, make sure Bluetooth® is turned off on those devices. (When you finish pairing your hearing devices to your Mac, you can turn Bluetooth on again on those devices.)
Above info. from : Use hearing devices with your Mac - Apple Support
How to: Change Hearing Devices settings for accessibility on Mac - Apple Support
__________________________
Re: it would be so good to be able to listen to sound from the MacBook without inconveniencing my husband AND without wearing headphones.
While not ideal, there is an alternative that may be useful in some situations:
About: macOS accessibility features for hearing - Apple Support has info. on using live captions
All the best :-)