Protection Paladin is powerful all around with their better tier set. They have a wide array of defensive cooldowns and do significantly more damage thanks to the tier set giving 15%~ more overall damage. Paladin's strongest point is their utility, particularly their ability to lock down caster mobs with
Avenger's Shield.
With the amount of defensives Paladins have, they can do well in any encounter even against magic, bleed and high burst damage.
Eye of Tyr,
Sentinel,
Ardent Defender,
Guardian of Ancient Kings, and
Divine Shield are all on short cooldowns allowing them to always have something up. With the amount of interrupts required in Dragonflight,
Avenger's Shield and
Divine Toll are even more powerful than before. Paladins also have a ton of other tools to support the team with abilities like
Blessing of Spellwarding,
Lay on Hands,
Blessing of Sacrifice making them really good at a lot of dangerous boss fights in Dragonflight dungeons. Paladins also have a ton of offhealing, so much so that we've seen some dungeons being completed at very high levels without an actual healer. The group support has proven to be extremely powerful in the highest keys done since season 1.
At the highest level, Protection Paladin will likely not be as good as Vengeance, but will be situationally better. This will be particularly noticable in situations that require multiple kicks like Everbloom. For most pug enjoyers, Paladins are amazing at carrying with the sheer amounts of interrupts and offhealing.