Why is FBX playback/import sooo slow

So how do people make videogames with these things?

A while back we had our animations created in fbx. Playing these back now in blender is extremely slow. This doesn’t seem normal at all. What’s the workaround here, what does everyone do? We’ve tried opencollada importer/export. It was the artist who converted his source file in max to opencollada. Importing it for him worked fine, except in blender, it was all spaghetti monster once imported. Same thing with .x format. Everything default blender-wise seems broken. File is around 10MB, 1K polys, 700 verts, around 6000 frames of animation, 17 bones. Much obliged any info on this.

The files came from 3dsmax 2016, rig and animations were combined in one file. Other source viewers like open3mod and our custom engine using Assimp are able to load the model just fine (fast import and playback).

computer specs i5, 16GB ram, gtx1060

short video showing the import and broken playback process.
<a href=“https://www.youtube.com/watch?v=dt5_1IhUB7c” target="_blank">
https://youtu.be/dt5_1IhUB7c

Here’s the .FBX import. 5FPS.