So that's just not true. I have an Emergency - have owned 2 of them over the years.
Interestingly enough the new Emergency has both the old and a new transmitter. So if it wasn't viable why would it have it? The frequency is still used for search and rescue. What changed is that the 121.5 mhz frequency was no longer monitored by satellites. It is still monitored via search and rescue services.
I actually changed the batteries myself following the instructions of this video I found online:
https://www.youtube.com/watch?v=H1BPc_gpk6U
$10 worth of batteries and some patience saved me quite a bit of money compared to the Breitling service.