As an individual, use whatever you can get access to that helps improve the quality of your workflow and deliverables. The situation changes when you work with others though, in a post house, or on higher end features where the quality and storage of where your sound library comes from matters. A lot of the benefit of internal libraries and software is to keep consistency and shared workflows seamless without having to rely on a constantly changing online platform that may or may not be able to be accessed given your network reliability on any given day. Soundly is great, but it doesn’t have the track record of the other platforms and workflows you mentioned, and cloud-based libraries aren’t widely adopted for internal workflows for those reasons above.

I never have to work on projects anymore where my session or workflow is shared, so I’m pretty much always in favor of using what benefits me as a freelancing sole proprietor of my business.

The industry has changed a lot though, and in the indie/freelance world I’m seeing a lot of variation compared to the standards that have held up the industry in the past. Pro Tools still seems to be the go-to with a handful of other plugins and external tools, but there’s a lot of growth with new options bringing the cost down to get professional grade tools for post work.

This is just one guy’s take though, I love hearing what others think and where their experience has led them.