Um, are you sure about that? I've seen countless games when teams run plays in end of games scenarios. Seriously, why bother calling a timeout if you're going to go iso. Most teams will design a play that may end up in an iso, but generally with a mismatch. If your play ends up with an isolated against the defender the other team wants, again, why bother - the opponent will fully cooperate with you anyway.
Yes. Teams rarely run a play in the last minute. They call timeout to a) get the right personnel on the court; b) go over defensive schemes by the opposition; c) make sure the guy who has the ball knows what his options are; and d) make sure his teammates know where to be on the court and what to do if the defence does x or y. If you've been in a basketball huddle, you would know this.
Again, whether it is Cleveland, GSW, San Antonio, Milwaukee, Washington, Toronto, etc., they will run one of two plays - ISO or high pick and roll, which is essentially done to create an ISO mismatch (e.g., Curry on Tristan Thompson in the Finals two years ago) or force the defence to double team (which they rarely do in these situations) and, thus, leave a wide-open shooter.
ISO is also often called because it's the safest offensive play. The likelihood of a turnover is low since the ball is your best player's hands. It allows said player to dictate the play and read-and-react. If it's straight-up one-one-one, he attacks. If the defence cheats or opts to double team, he makes a quick swing pass. His teammates, though, need to react and be in the right spot.
Recall, for instance, Game 7 against the Nets and Lowry had the ball. The Nets ran a double team at him. Ross was suppose to be the outlet but he went to the wrong spot and Lowry was forced into a tough shot.
If there is less than 5 seconds on the clock, a team likely runs an out-of-bounds play because, well, they don't have much choice.