Will Garmin Connect ever get an update?

I hope not. I like it the way it is. There have been minor updates but sounds like you want a complete overhaul.

Its not bad.  But there could easily be many improvements.  Some the simplest things are not possible.  Example, you can see report trends for various data, but you can only show at a maximum 1 year at a time.  I would like to see multiple years at one time.  I don't mean displaying 1 year and then scrolling back to previous years.  I mean I would like to be able to set the time span to say 5 years or whatever arbitrary span I desire.  

 Another issue with report trends is sometimes the scaling of the data is useless.  Take running pace.  It scales it arbitrarily without much regard to resolution or average.  If my pace is around 10 min/mile but the scaling is 0 to 15 min/mile, it is hard to see variation.  Why cant they scale it around the average over the time period you are looking at?  Like 9 - 11 minutes?  In addition, the trend for say 1 year just shows conglomerated data for each month.  Why not show a data point for each individual activity?  Or even better have a switch to go back and forth?

There is a gold mine of data I have since 2016, but Connect is fairly poor at presenting it.  Its like - hey, there is a mountain of gold over there free for the taking.  Here is a broken plastic spork, go dig it out.  There are many things I would change/improve/add.