https://www.thenation.com/article/world/why-netanyahu-bolste...
"Releasing Palestinian prisoners, allowing cash transfers, as the Qatari envoy comes and goes to Gaza as he pleases, agreeing to the import of a broad array of goods, construction materials in particular, with the knowledge that much of the material will be designated for terrorism and not for building civilian infrastructure, increasing the number of work permits in Israel for Palestinian workers from Gaza, and more. All these developments created symbiosis between the flowering of fundamentalist terrorism and preservation of Netanyahu’s rule."
The idea that these points prove that Netanyahu purposefully bolstered Hamas is tenuous at best.
And also worth noting, there's internal Israeli politics involved in all these reports - Netanyahu wants to show that the failure was on the military/intelligence side and not on his side.
It is completely baseless to claim that Israel knew about the attack and let it happen - no serious person is suggesting that.