The beauty of VBA is that it ships with the sheet and does not require the installation of additional programs.
The need to use an add-in means the majority of excel users (accountants, engineers etc.) are unable to write their own scripts without needing an IT department to approve, install and distribute the add-in. In most corporations this means the JS API is just not an option.
Our only options then become to learn VBA while its on the way out or use Google sheets which lets you do it all online (ie no installation/IT department required).
Ultimate goal = One engineer writes a few scripts in a sheet and is then able to email the sheet, with functionality included to another engineer who can open and use it immediately.
not to be rude about it but this seems like a massive security vulnerability just waiting to happen