Sealed doesn't guarantee good condition as you can't gauge centering and various other details. You would need grading to get the real condition, which requires it to be unsealed.

collectors want the sealed condition for rarity sake.

Again, we can't look at a lot of TCG product as this is a set of static cards and the decks don't change. It's more akin to Lego collecting where an unopened set can fetch a premium, but the opened product (especially the pieces only in that set, which the Ira cards count as since they are labeled as the Ira set) still fetches a good amount.

So graded, sealed, or even unsealed and ungraded all shows long-term collectible value (assuming FaB popularity continues and this hype isn't a bubble).