What's interesting is how fast they demolished the guide stones, they said it's due to it being a hazard to the public
Come to think of it, it is kind of odd how quick they were to demolish the whole thing.
I think you're forgetting how heavy these granite pillars are and the capstone - from wiki:
PHYSICAL DATA
1. OVERALL HEIGHT – 19 FEET 3 INCHES [5.87 m].
2. TOTAL WEIGHT – 237,746 POUNDS [107,840 kg].
3.
FOUR MAJOR STONES ARE 16 FEET, FOUR INCHES [4.98 m] HIGH,
EACH WEIGHING AN AVERAGE OF 42,437 POUNDS [19,249 kg].
4.
CENTER STONE IS 16 FEET, FOUR- INCHES [4.98 m] HIGH,
WEIGHS 20,957 POUNDS [9,506 kg].
5.
CAPSTONE IS 9-FEET, 8-INCHES [2.95 m] LONG, 6-FEET, 6-INCHES [1.98 m] WIDE; 1-FOOT, 7-INCHES [0.48 m] THICK.
WEIGHS 24,832 POUNDS [11,264 kg].
6.
SUPPORT STONES (BASES) 7-FEET, 4 INCHES [2.24 m] LONG 2-FEET [0.61 m] WIDE. 1 FOOT, 4-INCHES [0.41 m] THICK,
EACH WEIGHING AN AVERAGE OF 4,875 POUNDS [2,211 kg].
7.
SUPPORT STONE (BASE) 4-FEET, 2½ INCHES [1.28 m] LONG, 2-FEET, 2-INCHES [0.66 m] WIDE, 1-FOOT, 7-INCHES [0.48 m] THICK.
WEIGHT 2,707 POUNDS [1,228 kg].
8. 951 CUBIC FEET [26.9 m³] GRANITE.
The blast to the one pillar that also damaged the capstone left this multi-piece monolith in a very precarious, unstable condition of multi-ton stones that could easily fall and kill people - and you know people were likely to flock to the site to see the damage. It would be beyond reckless to not take the entire thing down once it was clear that proper support had been compromised.