The short answer is yes for most people.
If you need to communicate with people you would most likely benefit from learning how to be a better public speaker.
The principles of public speaking are principles of communication. That includes persuasion, teaching, inspiring, informing, reporting and leading. Many techniques from public speaking can be adapted to other forms of communication. That includes one-on-one conversations, phone calls, interviews and meetings.
Here are a few examples of non-business pursuits where public speaking skills can help:
Government bureaucrats, managers and staff speaking to the public
Medicine – teaching, advising and advocating
Individuals speaking to City Hall council or committees
Non-profit associations presenting their message
Artists explaining or promoting their works
Scientists asking for research funds or explaining their results
There are certainly more that you might be able to think of.
The point is that most people both within and outside of business can benefit from learning public speaking skills.
Learning to improve your public speaking skills will also train you to think more critically about how you convey your messages and help you connect with people.
Remember that every time you speak in public you are practicing public speaking.