Question about the Emperor.

To preface this, I am by no means even barely tapped into the rich universe of Warhammer 40k. I only started getting into it when SM2 was available on the PS+ subscription. Since then, I've been watching lore breakdown videos on Youtube about the different factions, Primarchs, wars, etc.

So my question is: Did the Emperor cause his own "downfall", as in spending the last 10,000 years as a rotting corpse on a Golden throne served as a life-support machine, because of his own neglect as a father?

I mean from the very start, he cut a deal with the Chaos Gods then going back on the deal, angering them; who then scattered his sons around the Galaxy; before finding them and making them swear to loyalty. He obviously saw them as tools to be expended, and that basically caused the Horus Heresy, and Horus himself crippled the Emperor towards the brink of death (I'm simplifying that a lot.)

What do you guys think? Was the Emperor to blame or was it all invetible regardless of his actions?