Did my opponent demonstrate the full might of the Caro-Kann in this game?

Introductory tutorials to the Caro-Kann opening often say that Black plays that opening if he wants to get a good pawn structure in the endgame. Well in this game that I lost, opponent had two impressive pawn chains by move 28, restricting the mobility of my bishop and two rooks. It didn't help that he had two knights for my bishop.

no

No
3...g6 is a side line, not bad, but not popular
5...Bxf3 gives up the bishop's pair without being prompted by h3. Better 5...Bg7
Your 7 exd5 releases the tension too soon. You trade your most central e-pawn for his not so central c-pawn if he recaptures 7...cxd5 Better 7 O-O-O same 8 O-O-O same 9 O-O-O

Gurgenidze system.

The Caro-Kann is a powerful weapon. I use it frequently.
But s/he did not use it the way it is supposed to be used.
After 3. Nc3, play 3...dxe4 4. Nxe4 and then play 4... Nf6 5. Nxf6 exf6 or 4... Bf5
A mistake I sometimes see people who are new to the Caro is playing 1. e4 c6 2. d4 d5 3. Nc3 Nf6?! 4. e5! and Black loses a tempo and White has a space advantage.

Not at all
You lost coz you missed some nice tactics

piece hang > pawn structure

bro, you hung a piece, nobody cares about the pawn structure in such a situation, I don't understand why low-level players are so obsessed with openings rather than putting to work on their tactical skills, which is what defines most games at their levels.

I've played the Caro kann hundreds of times and I can tell you that, that is far from the full might of the Caro kann

Gurgenidze system.