The question mentioned is five years old, has no votes, and has three answers. Does its age preclude it from being flagged as a software-rec, or should it still be flagged?
Short answer: see Oliver Salzburg's.
Longer answer: There are 10s of thousands of old questions that are now off-topic. They might be viewed as bad examples, and some of them as "diluting" the quality of the site. However, they aren't really doing any harm if they're just buried.
So it doesn't make sense to search them out and close them all. It would create a massive review job. It's difficult to keep up with just the new questions, and the effect would be like spitting in the ocean. However, it's different when they attract new poor answers and steal exposure from new questions.
When you come across one, first assess its potential. Many questions request a software recommendation because the OP isn't aware that the problem can be solved without it. Decide whether the question could have value if you edit it to simply request a solution to the problem. (If it's old, with no votes or favorites, low views, and the answers are just low-effort, low-quality software recs, that's an indication of its value.)
If the question has no real value to anyone else, or can't be edited to make it on-topic, flag it. That's especially true if it is attracting bad answers (e.g., the reason you found it was because someone bumped it into the active questions by posting a new, link-only software rec).
Flag it. It should probably be removed.
Many people here use downvotes to show something is wrong, this includes alerting the poster that the question is off topic.
Flag it but, IMO, it shouldn't be downvoted. If anything, I'd love to see as soon as a vote is cast, the voting is locked to prevent this, although I am aware that this wouldn't work for many other reasons.
Yes please. I frequently see low-quality software recommendations (borderline spam) in the Late Answers queue from low-rep or new users. Such posts don't really serve a purpose, and when I come upon them, I vote to close the question, no matter how old it is.
If we close these questions before the dubious posts come flooding into the answer section, we save reviewers time and make Super User look better - devoid of sketchy links.
This is my thought - If it was voted for and replied to with "relevant" answers there's some good to it.
But, given that now there is "Software Recommendations" Site on stack exchange in addition to Super User it should ideally be moved there.
Funny thing is, I had no idea Software Recommendations had come up as I primarily remember good ole holy trinity :)
I had a similar quandry when I posted this few years back in Productivity as Software Rec did not exist and Super User was not a good fit as it was related to better life & schedule management.
PS: I'd be curious to know what would be the ideal place to post it now?
I still do not have a conclusive answer.
There are times when a post may be equally apt for 2 SE sites. Better to find a better fit & move the thread to a better location, than to delete & trash the collective efforts of people.