For starters, the NBA playoffs are currently underway, and the Blazers are not in it. Because of this, I will assume you are referring to next season.
You say they will make the playoffs because they have Damian Lillard. I fail to see a connection. You have to prove to me that Damian Lillard is so good as to make the team he is a part of automatically make it to the playoffs.
Also, the very fact that they are not in the playoffs this year when they had Damian Lillard nullifies your argument.
I'll leave it at that for now.
Again, my opponent is just listing off players that the Blazers have. Nowhere has he given any reason as to why the players on the team make the team a playoff contender. You may say that the players you listed were good, but I can say the same for the Mavericks, who have Vince carter, Dirk Nowitzki, Oj Mayo, and Shawn Marion, three of which have been an all star. That however did not guarantee them a playoff spot this season. You could also make the case that Damian Lillard won the Rookie of the year award, thus propelling them to the playoffs, however Kyrie Irving was also the Rookie of the year last year, but his team was no where near the top 8.
I think it is clear to see that my opponent hasn't provided a shred of convincing evidence to prove his claim.