When I use opera max on my phone I lose 20-30Mbps of speed on my connection. I expected some loss BUT not that much. Also a little disappointed it's not changing my IP address
Opera Max is a compression service. It will slow down your network because it is using a vpn to tunnel everything sent to your device.
As for your IP not changing, That is with Opera VPN: https://www.opera.com/apps/vpn
You can download it and it will Block Ads, Trackers and Change your IP with your desired country.