I'm gonna throw a very wild idea out there... I wouldn't be surprised if people think it's nonsense, but whatever. Try and stick with me, I'm gonna take sports as a reference here. Let me take tennis as an example.
Tennis has indoor and outdoor matches. If you look at it, one could easily argue that indoor matches are the only matches that are a reliable way to determine a player's skill, because there is no wind screwing with the direction of the ball, and everything that you do with the ball is gonna be in your hands, and where it falls is where you actually hit it. Outdoor courts can have wind and rain, birds or squirrels or whatever messing up the game and so on. There are so many variables there. The wind can spike up at any time, a dust cloud can hit your eyes blinding you from where the ball is going, you can hit a ball that would fall perfectly on the line and the wind blows it to fall outside, the sun can be in your face and so on. However, if you look at it, the skilled players are able to adapt to all the wind and dust and rain and so on. The one who wins, be it outdoor or indoor, is considered the better player.
Now on to DOA. In a way, offline is the indoor court, and online is the outdoor. With offline, everything is set and it plays very differently from online. For online, you have to compensate for the variables, lag spikes, increased input lag and so on. Would you imagine how retarded it would be for tennis players (or baseball players, soccer players and a bunch more) to say that only indoor courts/fields are a viable way to determine the skill of the player/team, because wind screws with the ball? Or to say that every outdoor player/team needs to be an indoor player/team, otherwise they don't matter? Why is it that it is somehow acceptable to do this in regards to DOA and fighting games in general? Why is it that everything is supposed to be a fixed calculation?
Why is it that people are so resentful towards online? Thing is, one who has always trained outdoor/online, will have an easier time adapting to indoor/offline than the other way around because they are used to random changes and can adapt on the fly. No one complains in tennis if the wind helps your top spin to go more outside the court to put your opponent more out of position than they would be, or if it actually blows the ball closer to you to catch a fly in baseball that you otherwise wouldn't be able to reach, or make it a home run that would've otherwise been an out, or made it a goal instead of a miss in soccer, but somehow, online tactics are demonized and propagandized to be this scandal that people should be shunned for using. Sure, there comes a point where online matches completely lose their reliability to determine skill, just like in sports a storm will force the match to be stopped. However, there is no real rational reason to say that online is no measure of skill or is no basis for a community. That is just a cultural bias in not only the DOA community but the FGC in general that actually needs to go. It separates communities unnecessarily and makes them appear smaller than they actually are.
On another note.. Online players should be more open to offline, and the other way around as well. However, most of the issue comes from offline players who want online players to adapt to them, but they in no way want to do it the other way around. Some even completely refuse to play offline, even with someone that has an almost perfect connection with them. Is it unexpected then, that people don't make an effort and in the worst case completely reject joining the offline scene, when you basically already rejected what they like or even ridicule them for liking it? Why would anyone choose to meet you, let alone join you when you make them feel like a social outcast?