Trimming activity messes up the stats for it on Garmin Connect

Whenever I trim an activity it messes up some of the important stats for that activity, thus removing a lot of the point of recording it on Garmin Connect!

A couple of examples:

-I just trimmed about a minute off the end of a swim activity as I'd not stopped my forerunner for a while at the end of it, and my "average heart rate" for the activity went DOWN despite that during that trimmed minute I was just resting and my heart rate had dropped back down to normal. This is clearly wrong - if anything the ave heart rate should have increased slightly.

- I often trim a few seconds off the end of cycling activities imported from Zwift, so that the activity ends as soon as I stopped pedaling rather than only after I've dismounted and gone over to my laptop to press stop (otherwise the average RPM, watts power etc would be inaccurate). However, doing this always makes the "elevation gain" reduce massivley to a very incorrect figure, and also the calorie count for the activity usually disappears from Garmin Connect entirely.

Is this a known bug in Garmin Connect? It basically makes using trim entirely worthless if so.