The modifications to ELO that the Splinterlands team made are entirely to blame for the bot flood.

Certainly has a lot to do with it at least.
Real true ELO is harsh and can be painful to many users... i think they tried to soften it's blow WHILE making up for not having real leagues. Which led to their bastardized system of elo that created a new set of problems some of which you described

I'm not sure most users are willing to see real ELO be used and ready to see their scores drop as much as they could. But hopefully after there are real leagues we try it.

Oh and so far I'm still a fan of collection scores but it really needs the real leagues thing so i think this in between time is gonna be a bit uncomfortable.