A big thing for me is that apt + pip means I know more about what I'm installing, whereas conda seems like it'll go off and do what it thinks is best. If it's going into production then I want to know why we need package X and how it's been installed, rather than "conda says we need it".
Basically, I think conda encourages "install and forget" which means people don't really know or understand what they're putting into production. And that can cause a lot of problems further down the line.
Also the fact that conda installs everything to sandbox causes it's own issues. Suddenly I have two versions of a system package. Now I've got to do extra work to deal with that.
Then again, it could just be I never got over the time where uninstalling anaconda ripped apart the python install on my MacBook. That's a weekend I won't get back.
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Also, Production shouldn't use virtual environments in my opinion. That's an additional deployment/build step which could fail one day. The container image is a virtual environment in and of itself anyway!