90c is not good at all, whether it's in a laptop or a desktop. The components can take high spikes at those temps, but for an extended period of time it's going to kill them prematurely.
Laptops usually have higher temps due to the compacted nature of the setup and the airflow disadvantage, but the sensitive parts still have the same limitations when it comes to how much heat they can withstand over extended and consistent periods of time.
If a person is experiencing unusually high temps in a laptop, the first thing they should do is make sure they're not resting a laptop with bottom air vents on bed comforters and restricting air flow (which is probably the case 90 percent of the time). Also, if the fans are giving out or are no longer operable, that's obviously going to have an effect.
Assuming the fans are still running and the vents are not being obstructed, one way to lower the temps would be to underclock the CPU and RAM, provided the BIOS provides that capability on the laptop. If not, there should at least a setting in the BIOS to have the fans run at high speed constantly instead of letting the motherboard control the fan speed in response to temperatures, should there be a faulty heat sensor or fan control module. Battery power would be affected somewhat, but it beats a dead computer.
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