Does it cost more to keep code in a standard format, with all it the dependencies needed to run it? Yes, especially if you replicate the codebase anywhere the journal article is stored so it has backups in case of disaster.

However, the costs are fairly comparable to what was once the cost of keeping paper copies for everything, so I think it is a cost that can be absorbed by academia.

It is not only about money, technology, infrastructure and people for keeping it running also play an important role.

You can run Apple II code in a browser, for example https://www.scullinsteel.com/apple2. A code format that has survived for 40 years and counting. This holds for plenty other data and code formats that were once popular.

Docker/CFI is very popular, hard to believe it will disappear short of a complete breakdown of the digital era.