Jedi can't block the amount of incoming pellets
There's absolutely no post-EU deletion canon to back this claim up, and plenty of canon that shows it's wrong, including High Republic stuff where Jedi force-deflect shrapnel and so on.
It's a bit of old-EU bollocks from the same bollocks-mongers as "Jedi can't stop a pistol because they'd just melt the bullets!".
Anything old-EU needs to be disregarded until recanonized. Especially as a lot of it was never even close to canon and often directly contradicted by other old-EU sources.
Gas and acid/liquids should work pretty well against Jedi as very few Jedi show much ability to control either - there are specific Jedi who can - Elzar Mann for example in the High Republic books can deal with gas and liquids, but a lot of other Jedi in the same books cannot (and Mann has a sort of sea-centric vision of the Force, which probably helps). Thermal detonators are "sufficiently large explosions" so yes those are a real problem.
Some force-users can also deal with flame - Grogu can, for example, and he's a child (though seemingly very powerful).
Basically the only good ways to defeat Jedi are:
1) Big explosions.
2) Surprise attacks - they have precognition but it's very short and doesn't seem to reliably work with stuff like traps/mines.
3) Wildly outnumbering them - most Jedi can only deflect so many blaster bolts for so long.
Anything else might or might not work based on the specific Jedi involved, so you're taking a risk unless you are familiar with their specific abilities and they're not the sort that would hold something back.