Reproducibility? What's that?
Grizzled old university sysadmin here, ex researcher. I spend a fair amount of time explaining to our researchers (and not all young 'uns) that basing their critical work on code grabbed via 'git clone <last night's commit of useful looking repo>' is not a good start. Most are honestly baffled at the impact this will have on reproducibility, and I seriously wonder if basic scientific methodology is not formally taught any more.
On the other hand freezing anything other than a very simple codebase and expecting it to continue to work for years afterwards is a very difficult problem to solve. The immense pressure to publish also relegates these issues to way down the list of priorities.
Bioinformatics is the main culprit in my experience as it's a new field and there's been an explosion in ad-hoc tools and pipelines cooked up in labs and released to the world and embraced with little concern for long-term maintenance and preservation. We're at the stage in bioinformatics software cycle where the initial burst of software activity of 10-15 years ago is leaving a lot of abandoned applications in its wake. Whole research programmes have come to rely on some of these and it's always painful explaining to them that they must find an alternative as their cherished application or tools no longer work due to our necessary OS upgrade.