This game's timers are far too generous. 99% of the time a player is taking a very long time on their turn it is out of spite. Because they can, because the timers are so long. There is no reason turn timers should be 30 seconds three times before you get an actual "rope" or turn timer for a single action. You also don't need what is it? 3 full minutes? Maybe longer? to decide whether to mulligan or not. There's a reason chess has reasonable timers. If players can't make decisions in a reasonable amount of time they shouldn't be given the opportunity to waste more time to make what, in most cases, is probably the same suboptimal decision they would've made with less time.
And to re-iterate, the vast majority of the time it's done out of spite, because the game's timers are so long that it encourages this toxic behavior to be a feature of the game.