People were saying the same thing about mobile phones and later about aircraft with lithium batteries but product development has moved on as it has with EVs.
FYI: (a) Most full hybrids are NMH (less subject to temperature extremes and cheaper than lithium (b) PHEVs and BEVs are mostly Lithium because of storage to weight ratio . These have elaborate cooling systems computer controlled: . -traction battery cooling system . -fast charger cooling system . -convertor/invertor cooling system
The phobia about battery fires now is similar to the phobia about mobile phones triggering fires at bowsers 35 years ago.
Statistically as per a post above ICEs are 61 times more likely to start a fire than a BEV and add to that a full petrol tank and you have enough firepower to take out the neighbours on both sides as well!!
FYI here is a summary of the article again:
Q: So how intense has one BEV battery fire to be to equal 61 ICE fires?