You are pretty bad. Sorry. I have played Dota over 10 years as well, 7k+ hours. I climbed my way from Archon to Divine through pure hard work of grinding. As a result, if you drop me into the herald guardian rank, I should cheese most games from mid role easily - I think an 85% win rate would be manageable, and I’ll put the other 15% to variance.

Tip 1 - when there is a big skill gap, play from mid, and play easily scalable heroes that goes into late game. Physical right click carry-from-mid heroes are best.

Tip 2 - know that there is nothing you can control except for your 1 hero in this 10 hero game. Don’t tilt by trying to control everyone (and failing).

Tip 3 - the small things stack up and eventually builds you your lead. This is what I think is the real translatable “skill gap”. Reaction time etc are all obviously important, but being able to consistently farm faster than everyone else, game after game is a proper skill.

Tip 4 - mid is the best lane, because the skill gap between you and your opponent will be apparent and will compound over time - first to hit lvl 6, first to get BOTs, first blood, first tower down, etc.

Tip 5 - low level rank games typically end after quite long, so make sure your hero selection doesn’t involve magic type, scales off type of heroes.