Sounds pretty annoying/awful. The S model is a little smaller/thinner and I think the T460 I have barely makes the cut with the chassis (it has a lot more plastic than I remember the T series having).
I think in most cases it's pretty easy to pry these things apart and swap the batteries out.
I think the T series is great. I have a T460 (bought off ebay for $140). I had an extra SSD, some old ram sticks I stuck in there and it works great. The dock off of Amazon cost me approximately 20 bucks. The CPU maxes and never goes above 55 C (idles 37-40) and runs almost all my dev tasks as needed. The laptop is approximately the size of my 13" 2015 Macbook Pro (my wife currently has taken that one). I have two headless machines with GPUs if I want to game (via Parsec or Steam streaming) or use GPU for Python notebooks etc.
I've run Fedora and a custom Debian setup in the past (and currently am using Void Linux). Things mostly work with no real issues.
I think perhaps the mistake is paying premium with new and shiny things that haven't stood the test of time is the problem here? If you buy cheap (something that is a known quantity also), you're less likely to feel the b urn of walking away from the shiny / expensive new thing, right?
Note: I also have the X230 (bought off craigslist for ~$100, 2 years ago) and have given that to my dad who has used it happily for years now.