I was lucky enough to acquire a Fenix 6S Sapphire mid last year and have found it to be pretty impressive. The watch software updates have generally been good.
However the Deezer music app has been awful. Basically it just doesn't work - the sync always fails within a minute. Lots of Connect IQ reviews say the same. Watch resets, downloads, many of us have tried supposed fixes but all in vain. And back in early December I opened a ticket with Deezer and demonstrated the problem but have since heard nothing. Whilst I certainly didn't buy the watch exclusively for listening to music I did want to use the feature for some shorter activities. Meanwhile another family member has a Forerunner 245M and is also experiencing the same issue.
Of some note is that there have not been any Deezer app updates since early December - it is really looking like Deezer are having difficulties or possibly may have abandoned the app. Deezer released app v2.1.7 on 18th April.
Garmin may be reluctant to make a public statement in this forum - but really should strongly consider changing some product capability statements.
Meanwhile it would be good to know how many others have issues with the Deezer app.
Edit: see latest comments further down thread.