I'm not personally a big fan of EVs (I much prefer diesels - especially the ones from the late 90s!) but the statistics do show that electric vehicles are less likely to catch fire than conventionally fuelled vehicles.
According to this university report, petrol and diesel vehicles are 20 times more likely to catch fires - however from research from other sources the numbers referenced in this figure are quite small - in the order of hundredths, so fires in any motor vehicle are quite rare anyway.
https://www.swinburne.edu.au/news/2023/ ... es-higher/
The main issue with electric vehicles seems to be that the fires are fuelled by the lithium-ion batteries, which naturally ignite more easily than diesel or gasoline. This does pose a safety threat - unlike with diesel buses, where the bus smokes for a minute or two before bursting into flames, electric vehicles smoke for a few seconds, then explode:
https://www.youtube.com/watch?v=T71cVhxG_v4
But hopefully more advanced fire suppression systems will be all that is required to increase the amount of time passengers have to escape. More emergency exits might also be handy - on many buses, the emergency exits are concentrated around the front.