Afaik you are wrong. Idk about Invidious but Piped proxies all traffic through the server so it’s almost like a regular proxy that people used before VPN was a thing. It stores user data if you sign up but it is not necessary and if you don’t do it, the data will be stored locally with an ability to make a JSON backup of it.
Mozhi is proxied through the server/instance you use.
Is it fully proxied though? Some custom YouTube APIs use instances but they only store your history, subscriptions and stuff.
I don’t get the question. How’s that related to Mozhi?
Mozhi basically acts as a middleman between you and the translation api, it doesn’t store any user data.
Piped/Invidious proxy everything through YouTube, except for any kinds of user data, as that data is stored on the server you use.
Afaik you are wrong. Idk about Invidious but Piped proxies all traffic through the server so it’s almost like a regular proxy that people used before VPN was a thing. It stores user data if you sign up but it is not necessary and if you don’t do it, the data will be stored locally with an ability to make a JSON backup of it.