Speeding up rendering of 3d mesh plots

I am using 3D Mesh to plot 500-1000 boxes to create a model of a building. I have a codepen with the data here:

https://codepen.io/connorferster/pen/eYwXvVG

For each of the boxes, I am providing a pre-computed i, j, k. However it is taking a while to load, as you will see in the codepen.

The size of the JSON data is ~1.3 MB on disk, which I did not think was very big. Is there anything I can do to speed up the loading in the browser?

There is another topic in the forum from 2017 with a very similar title, but the advice given there was to provide the i, j, k instead of computing the alphahull. I found no difference in load time between using the i, j, k and the alphahull=0 (but alphahull=0 looks a bit better).

Previous topic: https://community.plotly.com/t/speeding-up-the-rendering-of-3d-mesh-plots-for-large-csv-files/4705

Grateful for any help or insight anyone is able to provide.