Is it worth delving deep outside my field to revise a paper? I have a paper that got lost in the editorial pipeline for about a year due to the second reviewer dropping out and not telling anyone.  During that year, I didn't revisit the paper much; it was a short, cute project that I whipped up quickly and didn't have big connections with my main body of work.

Recently, it got accepted with what the reviewer calls minor revisions.  The revisions do not seem minor to me, however, as they would require in-depth knowledge outside my main field; furthermore, some of the questions the reviewer poses would spawn projects by themselves.

The pre-print has already been cited several times, so I know the core idea has utility and appeal in the larger community.  It has also been relatively well received when presented at conferences.  It is of course in my best interests to get the paper officially published, but is it worth delving deep outside my field to appease this reviewer?

For cultural context, let's say I do numerical methods for nonlinear PDEs, and the revisions would require a dive into machine learning literature.  Also, I'm an early-career researcher.
Do you have a colleague or someone else you can ask who is an expert in the field you need? It is possible that with expertise in the area the reviews are very minor and a one hour talk with the right person will enable you to do whatever the reviewer suggested. Even if some of the reviewers ideas do take a lot of work this should enable you to satisfy some of the reviewers requests and come up with a reason to not do the others. Finally, if some of the questions create new interesting projects this might be worth going into, especially with a new collaborateur.