I cannot land on a summer internship. What's next?

I am a PhD student in a 10-ish food science program in the US.
I have applied to 10-20 R&D summer internships at food companies and only heard back for interviews from 3 companies: one rejected and two ghosted.
I have a good GPA, and 3 papers published.
I have 2 years of work experience in the food industry, but I doubt if it can help me find a job in the US since it was not in the US.

I know some say internships are not necessary for grad students, but I am not quite sure.
Are the job market and internships for food scientists in the food industry so challenging rn?
Is a PhD harder to get a job than a BS and MS?
I just feel so discouraged.
If anyone could give a piece of advice or share your ideas, I appreciate it.