For team games there were some issues. The devs are trying to fix these, but this solution creates new issues. Also they only fix the calculation. They still have to clean up their mess. For more info about these issue, see: Analyses of the ratings - Spotting the issues. As result of this issues the TG rating is inflated. As result you cant really compare a 1v1 rating with a TG rating.
The 1v1 rating is pretty accurate to me. There are some small exceptions. These are most like new accounts. They will play much worse or better then their rating suggests. If you start playing 1v1 if you already have a TG rating, then your initial rating wont be 1000, but the TG rating. As result of the inflation that will be far to high. Such player really have to drop in elo before it play against equally skilled players. In my opinion is this one of the only flaws in 1v1.
Since you are about 1050-1100 you might play against multiple players that do have a TG rating and start playing 1v1s. Their TG rating is high, but in practise they still suck. If they havent played 10 games, then you cant see their 1v1 rating. If you look at their profile you see the TG rating, which is much higher.
It is pretty common to skip loom in your build order on Arena. Just add another villager or just go up 25 seconds more early. I do this in all my games. As result i know i have to research loom before i can really castle drop, but sometimes i make the mistake and just forgot loom. Sometimes i even notice that i am in imp without loom.
These things might be the most common around this level. Players around this level start knowing the basics, but dont understand it fully. As result you have many players that are good in just one thing. If you play at a different map or if you have picked a counter strategy, then they dont really have an answer, even if they are the higher rated player.
You can also look at someones elo at AoE2.net. If the claim they were above 1100, they can also lie.
There is also some variance in how people play, so everyone within 100 elo range (something like that) can probably win on a good day.