obviously, yes!
in all honesty i don't really care as long as the music is decent. lip syncing doesn't bother me that much as long as you're trying to put on a show (Britney, Beyonce sometimes, Cheryl, etc.). I think some artists would benefit from doing it more tbh (Katy

).
Selena could fit into that category if she worked more on her dancing & visual elements. I respect that she at least attempts to sing live most of the time even if it's tragic since she doesn't have the other stuff backing her up. Rihanna can also probably be thrown into here although she's slowly improving over time.
With that being said, I still appreciate a good vocal performance. Rihanna at the BBMAs, Adele in general, Mariah in her prime, etc.