Spurs have the same match-up weaknesses as last year, they do not want to face against a big or athletic team.
The Grizz had both of those advantages. For some reason everyone underates just how athletic the Grizz were especially in the backcourt, they were like pitbulls and the Spurs looked like they were playing in slow motion compared to them. The Grizz frontcourt had size, depth, and youth that overpowered and frustrated Duncan/Dice/etc, and the Grizz bigs were even good at midrange too. Luckily there are no Western teams that are as athletic and big as the Grizz were last season, and the Spurs do have Leonard/Splitter playing significant mins to help.
But the Spurs need another legit big and health to truly contend, sounds like the same old song and dance for the past few seasons. They could also use good old luck, the Lakers size is going to be a nightmare