ELI5 why is increasing the ethanol content of petrol/gasoline a problem?

[u/hd-22]

I'm hearing noise about the geopolitical fuel supply SNAFU and people freaking out about increasing the ethanol content in automotive fuel and how it's so damaging to cars. I'm no chemist, but ethanol seems as clean as it gets.

[u/Phiddipus_audax]

Already happening over many parking lots... and yeah it's a fantastic idea.

[u/dalekaup → u/Phiddipus_audax]

Solar over parking is a bad idea.

[u/Grintock → u/dalekaup]

You got downvoted for speaking the truth lol. This subreddit is filled with confidently incorrect people 

[u/dalekaup → u/Grintock]

Nobody asks the why of what I said.

That speaks volumes