When applying for design roles in tech, what is the difference between product designer, UX designer, and interaction designer?
These titles are basically the same. The exact definition may change per company, but all of these require similar skillsets in research, interface/experience design, and visual design.
At Google, for example, roles under the UX umbrella are interaction designers, visual designers, motion designers, UX researchers, UX writers, and even UX engineers. Each of these roles are more specialized to a particular aspect of the UX process and have varied day-to-day responsibilities, which is typical for larger companies. Smaller companies may require their designers to take on all of these responsibilities.