Is this possible to automate?

I know the Icon Pixel Preview isn't set up to work with pages (which it really should be), but it's impossible to work effectively with a large icon set having to have them each in individual files.

File>Import has an option to do this.

"Add the SVG as a new page(s) in the current file"

If you have previously selected the "don't ask again checkbox", then you have to do into Edit>Preferences>Imported Images>Ask about linking and scaling when importing SVG image. 

Check that box in preferences if the dialogue does not pop up with options when importing an SVG.

Either you missed the part where I have 900+ SVG icons to import, or I am missing the part where I'm able to select more than one file to import? 🙂 Maybe it's a Windows dialog limitation and I have to try on Linux?

Also, is there no panel for managing pages? They don't seem to appear in the layers panel either.

Yes, on Ubuntu you can select multiple files click the first one, then hit shift and end.

Pages where introduced in the main Inkscape program in v1.2 so development is ongoing.

I have an extension which imports svgs as pages.

However - the question is how would they be imported - it's very difficult to scroll through 900 pages if they are imported on the same horizontal plane.

It would need to be a 2d matrix. 

I think a better idea would be to import SVGs to a symbol set. 

Then the svg can be saved and pasted to the Inkscape symbol folder. 

However I think 900 svgs might slow down performance