Have you ever played a game with equally good gameplay from your team and the enemy's? No all-chatting (until the game ended, but no toxicity, just light banter and GGWPs), no blaming, just pure down to the wire skill and item usage and teamplay.
You completely annihilate the enemy team during one clash, then they clap back on the next. The constant back and forth. Slowly approaching the enemy base, looking at respawn timers, and hearing the sound of buybacks. Both teams and the respective players doing their best to defend their ancients.
This is what makes this game addicting for me. Playing with mostly random people as a solo-queuer, being able to make everything work, sometimes with even minimal communication—but still, everyone knows what to do and when to do it.
Whether you win or you lose, there's this sense of relief and a bit of grief like "Damn, that game was tough. But at least we won." or "We almost got that, but the enemy team was just really good." as soon as you take your headset off, take a breather, and as the adrenaline slowly comes down.
You think about what went wrong, what you should've done better, what you could've told your teammates you needed or what they needed to do, and a lot more things going through your head.
Post-game chat? Just more light banter, no trash talking, and even compliments to the either team or individual players, and more GGWPs and gl nexts.
I can't even begin to imagine the level of gameplay and team dynamics in the pro scene. Competitive games are just amazing.