Q: How do I respond if I received a minor/major revision but the major points do not include valid arguments?

Some aspects of your question were not clear. So, I have edited it for clarity. Also, you seem to have brought up several points. So, let me first summarize the situation.

• Comments: You seem to have received comments from two reviewers, one for a minor revision and the other for a major revision. So, there is a conflict between the two reviewers regarding the number and kind of changes to be made in the article. Also, according to you, the major revision comments do not all seem to be valid or well-informed.
• Status: Based on the review comments, the editor has put the article in the Under Review status. Now, for most journals, Under Review means that the article is undergoing peer review. For some journals, it means that it is undergoing an initial journal and editorial check. In this case, after the article has undergone a peer review, Under Review could mean either or both of two things:
  • The editor is going through the comments to decide the next steps.
  • The editor has decided to or has already sent the article to a third reviewer as a way of resolving the conflict.
• Your action: There seems to be no action needed from your side yet, but you are concerned over the decision on the article.

If the above is an accurate understanding of the situation, here are the recommended next steps.

• Be patient: If the article has indeed gone to a new reviewer, you will have to wait until this review process is entirely complete. This means that once the reviewer completes their review, the editor will go through this reviewer’s comments and decision, weigh the comments and decisions by all reviewers, and then make their own decision on the next steps for the manuscript. As you can understand, this entire process will take some time. So, you will have to wait patiently during this period. At the most, if the editor hasn’t got back after a few weeks, you may politely request them for an update.
• Understand reviewer conflicts: Given this situation, your revision may involve making changes based on comments by three reviewers and may therefore not be a simple ask. While this is not an ideal situation, reviewer conflicts do happen. Here are a couple of previous queries around this situation:
  • How can I deal with conflicting editor and reviewer comments?
  • Does my paper stand a chance if it has received conflicting comments from two reviewers and has been sent to a third?
• Revise based on the conflicts: As mentioned above, revising a paper with reviewer conflicts can be challenging. However, we have an excellent resource on how to handle this. So, go through the following piece and follow the strategies described herein: How to deal with conflicting reviewer comments (Case study)
• Modify and submit to another journal (if needed): From what you have described, it seems the journal is at least somewhat interested in your paper. However, in case they end up rejecting your paper, do not worry. Based on the comments from this journal, you can always revise your paper and submit to another journal.
• Build academic resilience: Finally, I understand your anxiety and eagerness. As already noted, this situation is not a straightforward one. However, such feelings and emotions are a part and parcel of the article submission and publication process. The best you can do is be positive, and in case of an adversity, learn from it and move forward. Which is why, to end, I would also suggest going through and following the recommendations in this insightful piece on improving your academic capabilities: 7 Secrets to help you build academic resilience

All the very best!