There have been countless questions on the topic of question bumping to the main page for tag edits. I won't review or rehash any of that. Here are two suggestions I did not spot as having been made before.
When a question is bumped for a tag-only edit, the current tags are plain to see on the question. Indicate on the question, by whatever means is compatible with the UI, that it is a tag-only edit bump. People can look at the question title, excerpt, tags, and editor name, and decide whether to open the question or ignore it.
- Every visitor to the main page doesn't need to review the tag edit.
- This would allow anyone who wanted to look at the question to do so with that additional context.
- People who might not otherwise have bothered to open the question, might at least give the tags a sanity check based on the information on the main page.
- People who want to focus on new posts and more substantive changes would have a mechanism for identifying items not important to them that they could skip.
- Or, spotting that the tags had changed, the presence of a tag of interest could identify it as a question they might not have bothered to look at before.
Have an alternate mechanism for low-risk, high-volume tag edits. Some tag cleanup is well organized in advance. The intended change is posted and discussed on the local meta site. Relevant questions are identified, and the retagging is done by moderators and trusted users, using the tag-edit feature that doesn't alter anything else in the question.
In such cases, there is very low risk, and potential benefit to completing it quickly rather than in drips and drabs over a long time. If there absolutely needs to be some level of review, that can be done by an alternate mechanism rather than bumping all of it to the main page.