Is the Nyquist plot useful in actual electrical engineering?
If you plan to master Control Systems that are a lot more complicated than an Op Amp or a SMPS, then you will want to master Nyquist Stability Criteria.  But you may not have to do it now, but when someone pays you to use.  But then you may not have the time to learn it then, due to time pressures, so if you like it, learn it now.

 

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