I personally don't think opening OceanLog as open source is the ultimate answer. What I would love to see is a published specification for the computers with the commands, timings and formatting of the data so other application and open source projects which support multiple dive computer downloads to have native access to the download data. As a software developer in the biz for well over 20 years, some of the biggest flops happen when terrible software is opened as open source and then a bunch of less-than-spectacular developers start sticking their less-than-spectacular code in an already unstable mess.
By publishing the standards and specifications for the computers open source libraries as well as closed-source native functions can be added to otherwise solid projects. Take for example Diving Log. While this is perhaps not perfect software, it is one of the best dive log applications I've used but it is currently hampered with lack of native download capability because of the closed nature of the dive computer hardware manufacturers.
Now, before I hear the argument of liability, remember that this is not for planning dives or any other risk-based function. This is simply the ability to download existing dive data for logging reasons. There is no life-support function here, it's simply taking a snapshot of what has already transpired.
I and a few other talented people have been working on an open source library but without the specifications and standards, too much of the work is based on trial-and-error and educated guessing. Having published specs would make the results so very much more accurate and reliable. However, until the specs are released, we must continue with the current approach.