I agree, especially with the second half of your comment. They are certainly more challenging than a pala or sorc.

They also have a harder time farming their own equipment. Moving through higher difficulties safely with them requires a lot of tactical thinking and situational awareness. Trapsins and summon necros can be played extremely safe, but require skill and patience. But both have to do a lot of risk mitigation on hell difficulty to survive reliably. If we were just talking Normal/Nightmare the Summoner Necro and most Druids would also be an option. While the risk with a sorc is a bit higher than with a paladin and she is more susceptible to enemy resistances she can offset that by being more efficient with her farming in general. As long as you have mana you can prevent most of the sudden deaths the game throws at you. The sorcs safety options consist mainly of teleport and her energy shield. Also the best allrounder class in terms of enemy types. Add to that some good options for physical resistance, healing and maxblock. The Paladin can get 75+ in all reisstances with ease and cheap equipment.

Diablo 2 resurrected classes tier list