Bear looks like a cool app, but it doesn't seem to support custom export formats that could be used to create a twee file, which would be the easiest way to do what you're thinking of doing. Though even that would still require a command-line compiler or Twine 1 because Twine 2 doesn't import twee files.
Bear does support wiki-style linking, so I'm not sure why you would want to use tags for linking instead of just using individual notes for individual passages and links to link between them. Ideally you would use Bear with a markdown-based story format, since Bear will render markdown but will only highlight wiki markup within code blocks that specify it. Since Bear can export to markdown, it would be possible to write in Bear, export all notes into one markdown file, and manually convert the markdown headers to twee headers.
Though it supports code highlighting, it's not expecting code in the middle of your text the way Twine 2 is, nor is it likely to highlight that code well even if you mark it as code and wiki markup, so it wouldn't be the most helpful UI for someone whose Twine story is heavy on the code.
So the answer is "maybe, if a heavy on the markdown, light on the coding, heavy on the post-processing workflow will work for you".