I must live in a different Holland, cause I've literally never heard of this, unless you mean around New Years with fireworks I guess

> blows up the others' house. Sometimes half the block along with it

Can you provide a source for this? I had a look but all I could find were a couple of scaremongering style media reports from ~2022 saying it's getting worse but no information about if any of the bombs actually went off or if anyone was injured.

Certainly nothing like "half a block" getting blown up "sometimes".

Is Holland that good at containing this "there's a huge problem with makeshift bombs" news pieces coming out in the open?

Those makeshift bombs are just fireworks bought in belgium