There are different schools of thought. And it depends on what the scope of the discussion is. If you’re talking about preserving PDF/A or PNG files, you’re probably talking about media preservation. If you’re worried that your important document written in some version of PFS:Professional Write (an obscure word processor from the 80s) being readable, conversion and access become a problem.

I recall working with a group of archivists where one camp was in favor of conversion to standard formats like PDF for certain documents, another wanted to preserve documents in the original format, and still another wanted to do both.

It’s a hard problem and purity of thought makes it worse.