Yes I just discovered this lastweek It worked fine from Linux.

I only had to patch script: https://github.com/ventoy/Ventoy/pull/877

I guess it will be valuable to ship this in distros no ?

I know back in the day, there was a very similar tool called SARDU [0]. It is closed source from what I know, so if that was your breaking point, fair enough.

EDIT: There have also been YUMI and Easy2Boot in a similar vein before Ventoy.

[0]: https://www.sarducd.it/

For ages, there have been Zalman enclosures for making ISO-based multi-bootable external HDDs/SSDs working this way and on a lower level. And iodd which are essentially the same (AFAIK Zalman rebranded them).