It's just paying up to it in cash, not in money on the cap. If the Lakers have nothing on their books next year except cheap rookie deals and value contracts... big fucking deal? If they miss out on all unrestricted free agents, they can sign a RFA to an overpriced deal with all that cap space and take a swing on a Jabari Parker or Clint Capela who could be a star; if that fails and the teams match, they can eat other team's salary next year in the trade market like Detroit just did, except they could do so even better since they have more space and wouldn't necessarily have to send out so much just to make the money equal or near-equal.

The Lakers fans that genuinely expect that PG and Bron are coming are insane, but the idea isn't soooooooo out of left-field. And cap flexibility is key for a team as bad as LA but with the structural advantages they have (top 1 FA destination sans context, tons of young, exciting players who might grow as role players along stars or get dealt for another star). Deal did what it needed to, and Clarkson on that deal is infinitely more useful to the Cavs this year than it would have been for LA ever.