Permafrost bolts not receiving damage increase from Projectile Acceleration 3.

Permafrost bolts not receiving damage increase from Projectile Acceleration 3.
It shows the added 40% projectile speed in the tooltip but it does not show a damage increase. The skill feels extremely weak also, possible other bugs.

Also: Concentrated Area nor Magnified area 2 effect the damage of Perafrost bolts.

Am I overlooking something, because it is not very intuitive for these gems not to work with this skil.

Not a bug, support gem alone does not increase damage.
"Increased and Reduction" and "More or Less" are different modifiers.
If you want to increase damage with that you want "Increased projectile speed" from the tree or jewels or any other source of increased proj speed.

I see, thank you. What about the case of Concentrated Area and Permafrost? It has the AoE tag but it does not gain any dmg.

A bit unclear but most likely concentrated/magnified area only apply to skills that generates aoe explosions like shockburst rounds, grenades, glacial bolt, heralds n such or aoe ground effects like gas grenades n stuff.

You could make conc/magn area work by using frozen spites on permafrost bolt though, not sure if worth because frozen spites got a delay and things will die by permafrost before it triggers. Try it maybe you like it.