1.1.1.1 obviously has nothing to do with the installation of avast or ccleaner.
It is an IP resolver like your provider’s or google’s (8.8.8.8 )
https://www.cloudflare.com/learning/dns/what-is-1.1.1.1/
Check the settings of your network card (TCP/IPv4), the DNS server used by default must be the one of cloudflare (1.1.1.1)?

Apart from that detail, I agree with you quite a bit, avast’s policy has become far too aggressive, but I think it’s wisely managed on their part between the pros and cons. :wink: