No point thinking about Salem, Ally, etc when it comes to wifi and seclusion (no offense to them, they're also my idols).
It's all ZeRo.
He's the guy who inspired me to think it's possible to be the best player in the world some 1000 miles+ away from anyone competitive. One year he gets top 32 at apex the next year he comes back and gets top 8; he was banned by his local scenes so he couldn't attend their tournaments. As someone who originally went to the US in 2009 and came back dejected at the lack of "skilled opponents" I could play to push me forward, it wasn't until late 2010 that I started losing my locals after never playing outside events, it wasn't until 2012 where I realised how wrong that was (combination of ZeRo inspiration and SoCal's Tyrant). I rounded off my career in Brawl as arguably the best in the country (Australia), I still had no one to play with and never touched wifi, but I was dedicated.
It's really all about mindset and planning. What do you get out of wifi? Why are you playing wifi?
Why does it even need to be wifi? CPUs are amazing if you know how to use them.
Playing to win and playing to learn are two separate things, always. In friendlies I'm never doing anything but reactive choices/on the spot thinking, I won't mix up certain things ever because optimal choices is what should always be executed in that context. How are you going to be comboing people to death in a real tournament match if you can't even 0-death CPUs? How are you going to learn a character's best options if you don't know what the best option is and how an opponent deals with the best option?
Losing is a fantastic thing too, because if you don't know why, you need to figure that out, there's always a solution and it should be a fun exercise.