Yes, it is is good the interviewer was engaged and had lots to talk to you about.
However, unless you were interviewing with the Dean of Admissions, the interview is a relatively small part of the admissions equation. The interviewer may give a positive review to the Admissions Committee, but the AdCom will evaluate many factors, and the interview will be but one.
Based on numerous conversations we’ve had with other boarding school families and admissions staff, the interview rarely is the reason for admission, but it can sometimes be the reason for a rejection.
Best of luck to you!