Maybe take a look at this free one online (Beegraphy on steroids! ;)

https://cables.gl/

Interesting.
I made the same geometry from scratch in Moi and when I export that as STEP it opens correctly in Rhino and Fusion.
But obviously it's not constructed exactly the same as the model in beegraphy, so maybe I can't compare the result.

I found a workaround and have notified the beegraphy-team.
By extruding a surface instead of a curve the export works great and can be imported in Moi, Rhino and Fusion.
Thanks for the explanation why imported CAD-data might differ in different software.