Of course the vast majority of people would treat someone they never met before with respect.
But that is not the case here because Mako2011 is at least somewhat known to members through his interactions with them at dpreview. Therefore it is totally reasonable for members who have had dealings with Mako2011 to decide for themselves how much respect they will give him here on dprevived based on their experiences with him at dpreview should he decide to become a member here.
If I used your logic then that means just because I have never met DonaldB in person then I should respect him here at dprevived........yeah right 😉 ............I think hell will probably freeze over first 😊
The idea that it must be 'earned' sounds like you'll start-off disrespecting them until you decide that they've earned respect.
Not in the case where I had no dealings at all with that person. See above.
In the case where members know Mako2011 through their dealings with him at dpreview and for whatever reason have little respect for him, then yes it is totally reasonable that Mako2011 would have to earn those members' respect back if he was interested in rebuilding bridges here on dprevived.
Now put the boot on the other foot. How about if you start chatting with someone and they disrespect you from the get-go. How's that feeling for you?
If they had reason to disrespect me from past experiences then I wouldn't be surprised. If I had never dealt with them before then it would reflect very poorly on them as a person.