First, because I'd be willing to give the Lakers something in order to secure a S&T. Second, because the Lakers would be inking a 6/6/22/24 deal rather than a 14x4 deal. It's not a given at all that they'll want to pay Clarkson that kind of money when they AREN'T flush with the space. Third, because the team can't go into this off-season playing it safe. They can certainly move on to plans B, C, etc. when they strike out. But they should be thinking of locking in a permanent piece or two under this lower cap as a main priority.
Eh, it wouldn't take a huge offer. They have guys like Amir and Jerebko on whom they'll have to make a decision before the moratorium and young guys like Zeller. Plus, they're in position to draft Bender. And of course, they could be a destination for Howard, Horford or Gasol. If they make the personnel sacrifices to keep him on board, that's fine. I'll take either of Johnson or Johannes any day. Again, though, you go in there swinging for the fences.
So why do I think he'd count as a home run? Because he pretty much checks ALL of the boxes. He's a great screener who can either pop or roll well enough to put pressure on the defense. He can defend the PnR, which is a much bigger need in the SL than blocking shots. He can defend in the post (as well as score there), which is needed given the remaining guys on roster. He'd benefit tremendously from having a more-defined role with the Spurs with better shots.
He seems somewhere between Tristan Thompson and Aldridge in what he tries to do on the court. Dude's just 24. He has a great chance to get significantly better. And as far as culture goes, if he can hang with Stevens' team, he should be good enough for Pop's. For the money he'll command, he should be a great value to the team. Getting any combination of Johnson/Sullinger/Gasol and Clarkson/Gordon/some other scoring guard would be go a long way to fixing this team.