Appeared in the same situation, but several months ago. Hope this post will be read/heard 

I agree it's a shame to give that much money and get stuck with the old software. The battery saver should definitely be put on all the models.

Condivido in pieno. Garmin fenix 5x plus ormai uno orologio già superato da tempo. 

I agree totally. What Garmin cares is selling new watches. Current customers are forgotten. Even their very expensive premium model customers are forgotten. That is how they have been working since the day one. Their software development quality is also worst you can get. Updates always introduce new bugs that are fixed or not. Battery issues are constant. I had Vivoactive 3, but after struggling with it for a couple of years, I had to dump it as there´s no way to prevent new updates coming in and breaking existing functionality and causing battery drain. In about three years (since Vivoactive 3) was introduced, they haven´t been able to fix even some basic stuff. Fortunately with Fenix series it´s possible to downgrade to some older firmware that is an important thing.

Because Garmin doesn´t care about their customers, I really think they cannot be successful for a very long time anymore. Old customers won´t be buying new products anymore because of so bad experiences and ripping of business model that they have. Forums are full of complaints, but they are not listening.

Would be really nice to get, for instance, battery saving options, so we would not need to manually turn things off. Also body battery would be nice, although based on some comments, it is not very reliable and accurate. That´s also one big issues with Garmin. You get lots of data, but it´s quality is pretty bad and you should not trust it. For example, sleep tracking is a joke. There is not even a little accuracy compared to reality. Of course, you don´t necessarily know it without comparing it to some medically approved device etc.

I would really like to see back-ported functionalities, but based on the previous experience, it isn´t going to happen unfortunately. It is Garmin´s business model and one of their fundamental "values". 

Data quality problems are not specific to Garmin, their sensors has decent quality for accurate measurements, but their algorithms sucks. For example, you mentioned a bad Sleep Track and it's really bad compared to other smart devices (hello FitBit!), but take a look at this topic. It seems that the Firstbeat algorithms do this job much better than the native Garmin's Sleep Track, even though they're not meant to do this.

That's why Garmin should take care of the software part for its devices much more thoughtfully than it does now. Especially when it comes to software updates for their "old" devices.

I’m totally agree with you !!

You are complaining on the wrong media.

This garmin forum is just a way for garmin to save money on customer support by letting users do the customersupport work for free.

Garmin does not read this (or very sparsely) and are certainly not going to act on it. 

I have a 3HR, 5X+ and 6X Pro Solar. I don't use most of the features as it is. The ones that are most important, like HR (which inputs to things like stress, body battery, VO2, recovery etc.), GPS, pace, altitude are imperfect. I don't need even more half baked things when the core functions are still lacking performance. I would far rather that Garmin completed the original features to work properly rather than adding yet more new features that may or may not work, sort of, if you're lucky.

If you have resources in the media or on Twitter, I would be very happy if you attracted the attention of Garmin to the problem. Unfortunately, I do not have them and I know for sure that the developers follow the topics on the forum and all that remains is to rely on them.

Software updates should solve your problems too. However, I'm not sure that the limitations of the watches will make it possible to make such accurate sensors as dedicated ones. This is the same as expecting from the phone the same picture as on a DSLR camera, despite the matrix the size of a match head.