A quick Googling confirmed that buses (Florida) aren’t allowed to turn right on red-got that. Can they turn right on one of those green right turn only arrows? The reason I ask is today I was behind a school bus in that situation, and the light is completely red, and he doesn’t move-okay fine. But when the right turn only arrow came on (when the perpendicular turn lane people made their left turns), he still sat there and didn’t go. Did he screw up (and almost make me late for my shift)?
Multi-person vehicles like busses do things like stop at all train crossings.
Many have bumper stickers that say “This vehicle does not turn right on red.”
It is all about safety for the occupants on board.
I would say that the bus driver was playing it safe by not turning on that thar green arrow.
“Better safe, than sorry.”
a right turn on green arrow might leave not enough room for a bus to turn. the nonturning lane still has vehicles in it that the bus would hit as it turns. when the ahead green allows that lane to empty then the bus has room for its rear in a turn.
Do you mean you think there was something happening at that time that made turning unsafe, or that the driver never turns on green arrows for some reason? The former would be sensible, but the latter would be the opposite of playing it safe.
Ridiculous. A green arrow is a green light. It indicates that those turning right have right of way (and usually that those turning right have unchallenged right of way). Ignoring a green light is not safer, as it is confusing and discourteous to other drivers, and a confused or offended driver is a hazard in his own right. The only excuses for not turning in such a situation are (1) if a spectacularly clueless traffic engineer has put a green arrow on a combined lane (right or straight) or (2) if the bus does not have clearance (in which case he shouldn’t be turning from that lane at all).
It appeared to have plenty of clearance to me (so as to not sideswipe those vehicles in the lane to its left), nor was the intersection poorly designed (the lane in question is purely for right turns) or the light sequences fubared (they put in the arrow several years ago to help improve flow-but even now there’s usually a big line of cars sitting there during the all-red part of the cycle).
Is it possible the bus was stuck waiting for a pedestrian in the crosswalk?
The city buses here do that. We’ve got a train crossing near me at the bottom of a valley, complete with lights and gates, and they still stop. These aren’t school buses. What’s the point of this?
He should have gone (unless there was a hazard that you didn’t pick up on), but you should budget more drive-time if a single red light almost makes you late for work. 
Incidences in the past of drivers trying to beat the crossing arm/signal. If they are required by law to stop every time regardless, then there is little chance they will try to beat a crossing signal or train. Ancillary benefit is they can visually see that the track is clear in the rare instance that a crossing signal is malfunctioning.
I asked a neighbor who drives a school bus in PA. She said they can legally turn in the red light - green arrow situation but their company policy is not to do so because on narrow streets the bus may enter the oncoming lane while making their turn and they don’t want to be in the situation of encountering oncoming traffic.
Or encounter someone making a u-turn from the perpendicular turn lane in front of them.
[What TF Am I Complaining About Mode] I actually live right across the street from work, but deign not to walk via the pedestrian signals because EVERYONE runs right turns on red in this state. So I instead have to make 2 U-turns.
This is not as rare as one would hope. Not only do signals sometimes malfunction, but very low traffic, and some private crossings may not even have gates or signals. They will all have the St.Andrews cross shaped sign, and drivers need to look and act for their own well being.
My late dad made a career out of repairing malfunctioning crossing signals and other railroad signal equipment. A couple of times when traveling, we encountered malfunctioning crossing signals and he would report them to the railroad that owned them at the next pay phone. (he didn’t live to see cell phones become ubiquitous) There are probably still a few relays on the old D&RG line that have my dads “WEF” sign-off on the repair tag.