Will a petition to the manufacturer have any effect?

Well, you can strike lucky. Years ago I bought an FM radio tuner made by JVC. It whistled under my favourite music station. I opened it up and saw there was no ‘multiplex’ filter - just a factory fitted bypass wire.
Contacted JVC in UK - their reply was ‘There are no user serviceable parts and opening the product will invalidate the guarantee’
So I wrote direct to JVC in Japan. In three days an envelope arrived containing the filter coil plus clear note on how to remove the bypass and fit the coil.
Radio worked beautifully after that, and still does.
I have felt well-disposed towards JVC ever since.

@ellisonvoice said:

Contacted JVC in UK - their reply was ‘There are no user serviceable parts and opening the product will invalidate the guarantee’

Typical, I wonder if JVC USA will reply the same

Well, top marks to Phonak for apparently checking out assorted tips and howls of anguish on this forum. That’s an excellent way to fine-tune product - direct input from actual users.

@DaveL said:

I’m very relieved that participation in this forum and helpful criticism has motivated Phonak to modify their product.

Correlation does not imply causation. But if you truly believe that Phonak is making major decisions based on a few dozen noisy folks on a forum, then I suggest you start a thread demanding a 50% price reduction.

Please share link to my petition and sign it Petition · We ask Otiсon to continue to support users with severe and profound hearing loss - Russia · Change.org7

Or you can give up.