I looked at your SketchUp model. It does have millions of edges. Nearly three million edges.
Many of those edges are unneeded and are just slowing things down.
Running an extension like CleanUp3 on your model would help.
How were these lighting and trus components modeled? Not in Sketchup I’d guess.
The trusses look like they should be very simple but they aren’t due to all the triangulation. Turn on Hidden Geometry to see it. There’s no need for that if the tubes are drawn as simple cylinders.
Running CleanUp3 on your entire model to merge coplanar faces reduced the edge count by nearly 30%. More could be done manually. Looking at the end of one of the tubes in your trusses, it is drawn as a 12-sided circle. Extruded into a cylinder, there should be 36 edges. Even after running the cleanup roiuting there are still twice as many edges due to the triangulation.
Another example of excessive geometry is some of the triangular gussets.
After running CleanUp3 the same gusset looks like this.
The hole still have a lot of excess geometry. It looks like the intent it to make it appear the holes was enlarged by rocking the drill. Maybe it was but is that useful in the way this gusset is used in your model?
There are also some elements that would appear to be overly detailed. For example these clamps.
Do they really need “threads” and the split pins? The other clamps don’t have threads on the bolt.
You could further streamline you model by making more efficient use of components. For example here is a component containing four gussets. There’s eleven of this one in the model because there are eleven of those cubes. Every set of four gussets on the cube is a unique component and each of the four gussets inside the component is a unique component. The same sort of thing applies to the tubes. It would be much more efficient to have one gusset component definition, copied to make fourfor one side and then those four copied to make the other five sets. On its own this won’t reduce the number of edges and faces for LayOut to render but it will reduce model file size and make the model much easier to deal with if you have to make edits. I expect the component structure in your model is due to whatever application the objects were originally created in.
BTW, you really shouldn’t need to keep the boneyard of components over on the left of the model. They are components so if you need more of them you can drag them in from the Components panel. Eliminating them from the model space will further reduce the number of edges and faces that need to be considered during rendering/updating viewports.
I also see you have some very large texture images/ Those will also slow things down.
I did my usual cleanup process when I look at models from others. Fixed incorrect tag usage.
and purged unused stuff.
After that and cleaning up unneeded edges, the file size is reduced by more than 60%.
In LayOut I notice you’ve modified the Camera properties for the viewport.This will prevent the viewport being fully updated when you make edits in the Sketchup model.
There shouldn’t be any need to modify the Camera properties for the viewports if you’ve set up scenes in the model correctly.
A 50% improvement in a day.