Answer:
They are still points, aren't they? Yes, they are added.
Correction: Actually no, points scored in nba playoff games are not added to the total points scored in a players career. Career points scored for a player usually only refers to the regular season and does not include the nba postseason or aka playoffs. It is because technically playoff games are considered exhibition games, so while stats are also kept for these exhibition games the exhibition games do not count towards a players career total. For example the nba all-star game is also an exhibition game, so any points scored during the all star game will not count towards a players point total for the season or his career. Same goes for rebounds, blocks, assists, etc.