That's probably better, but also that's not much different on a conceptual level from a "filesystem". Both contain multiple files, and describe where in the overall image those files are. The difference is exactly in the interleaving - a multiplexed media container is somewhat constrained to a packet-based scenario, where individual packets of the constituent files are separated so that video, audio, and ancillary data all reach the decoder at roughly the same time. A pure filesystem is not constrained as such and can put the files anywhere within the container.
A filesystem stored in a monolithic file is not so constrained. I work with Harmonix games as a modder, and they use a bespoke format called "ARK", which is a two-part format. There exists one or more "ARK parts", which in implementation are virtually concatenated, and then the HDR lists a binary offset from the beginning of the first ARK part to tell the games where the individual files are. This could also be called a "container" conceptually. But none of such files are interleaved in any way except for the audio files, which use encrypted multichannel Ogg Vorbis streams plus a bespoke header to aid in seeking.
Plus, the context was explaining it to laypeople, where the specific jargon is less important than imparting knowledge and understanding.
A filesystem stored in a monolithic file is not so constrained. I work with Harmonix games as a modder, and they use a bespoke format called "ARK", which is a two-part format. There exists one or more "ARK parts", which in implementation are virtually concatenated, and then the HDR lists a binary offset from the beginning of the first ARK part to tell the games where the individual files are. This could also be called a "container" conceptually. But none of such files are interleaved in any way except for the audio files, which use encrypted multichannel Ogg Vorbis streams plus a bespoke header to aid in seeking.
Plus, the context was explaining it to laypeople, where the specific jargon is less important than imparting knowledge and understanding.