I first noticed that TNT can destroy blocks farther away than minecarts. To test this properly, I recorded the damage that I receive at point-blank range. I used Resistance IV so these explosions would deal damage but not kill me.

How to reproduce:

1. Surround yourself with obsidian, or another explosion-resistant block. Be sure to place a block above your head to prevent fall damage.
2. Use /effect @s resistance 1000 3.
3. Use /summon tnt ~ ~ ~ and notice that it deals 10 damage (this would be approximately 50 health without the status effect).
4. Use /summon tnt_minecart ~ ~1 ~ and notice that it only deals 5 damage (roughly 25 without the status effect).

For comparison, creepers deal 8 damage at point-blank range with Resistance IV (roughly 40 damage without).

I expected TNT minecarts to deal 10 damage, like the TNT. This damage reduction may be intentional, but I figured I would report it.

Edit: According to the Minecraft Wiki, a TNT minecart has a more powerful explosion if it is moving faster. When I tested this bug, the minecart was always stationary. So this could be completely intentional.