How important is a "Thank You" note after an interview, and is a text or email sufficient?

A "Thank You" note or letter is always appreciated since it reflects manners and proper business etiquette. However this is usually more of a requirement when a formal interview takes place - whether an online video or in person meeting. Casual, brief introductory phone calls are not considered a formal interview, and a "Thank You" note is typically not expected.

However the "Thank You" note can also serve as an opportunity to reinforce your interest and qualifications for the position, and to help solidify the next steps for a meeting.