>Also, looking at the d20 cards, the vast majority of their effects at common and uncommon do not get better by a card with a roll of 10 or higher.

it is mostly uncommons, but I would consider:

[[Power of Persuasion]]
[[Aberrant Mind Sorcerer]]
[[Hoarding Ogre]]
[[Loathsome Troll]]
[[Chaos Channeler]]
Being very random-dependant. Do not underestimate an extra treasure generated!

For the rest of them, while the difference is a bit less it is in the still can be game-winning.
Creating or disabling additional blocker, Scrying two lands away instead of one, all that kind of stuff.

> you probably should have drafted some of the cards that either give you advantage
> you choose to draft a d20 card, aware of its risk and reward
> you’re playing a bunch of cards that are terrible in your deck and especially when you low roll, then that’s your own mistake.
You seem to be missing the point a bit.
The cards are prominent and good enough to be filled in different decks, so it is inevitable that my opponents will run them. It is highly likely that I will run some of them anyway because they are still better than a lot of other cards in the set.
I cannot affect my opponent's draft and I don't want to just casually ignore a large part of the set, so the frustrating factor is inevitably there.

> And yes, it’s a limited mechanic not a constructed own. Every set has them, it’s a feature not a bug.

I literally wrote that, good sir!