Generally speaking resistances are still very desirable and good in LE, but capping them is definitely not mandatory compared to games like PoE or GD. The emphasize is on capping.
Resistances are still very good, because they protect against Hits and DoT’s and are easy to come by.
But if you for example have 65-70% resistance and you want some additional defenses on your gear getting another defensive suffix instead of capping that one resistance is definitely worth more.
If you want more concrete numbers I like to demonstrate this with a couple of small and well digestible numbers.
| Incoming Damage | Resistance | Damage Taken PoE/Grim Dawn | Resistance | Damage Taken Last Epoch |
|---|---|---|---|---|
| Area Level 75+ (Enemy Penetration = 75%) Applies after capping | ||||
| 100 | 0 | 100 | -75 | 175 |
| 100 | 70 | 30 | -5 | 105 |
| 100 | 75 | 25 | 0 | 100 |