Not sure how much I agree with that,
2 goals 1 assist in 369 mins played last season, that gives him a 1 minute goal contribution per 123 mins played
For comparison Morelos was at 1 goal contribution in 119 mins in the league and 1 in 158 mins overall (cup +europe+league)
Kent who we can all agree had a brilliant season was 1 in 159 in the league.
I respect that stats don't mean everything, Defoe played in the easier games etc and he obviously can't play every single game, or even the full 90 mins like the other 2 mentioned, but I don't agree with him being "done". He clearly still has an eye for the goal and that's valuable. If Defoe had half those chances Morelos had today he would have scored at least a few.
Defoe still has an admittedly small part to play for us. Today was one of those games.