The only way reset!classic is the same as casual mode is if you reset every time you lose a unit. That leads people to ask, "Why not just play on classic mode if you're imposing the same exact limitations of classic mode on yourself?" Essentially, it's because you use casual mode as a safety net. Say, you're about 40 minutes into a chapter, you have it in the bag, just need to finish off the last few units, then one of your units gets offed by a 3% crit. Yeah, I can see not wanting to reset in that scenario. You already bested the chapter, you just got fucked by RNG and don't want to take the time to do the entire chapter over again just to save one unit. Some people don't have that kind of time or feel the need to mercilessly punish themselves when playing video games. I mean really, what do you get out of doing so? Bragging rights? No one gives a fuck. No one cares that you beat a game on lunatic classic. Honestly, anyone that does really needs to get a life. On the other hand, if you're about half way into a mission and you lose a unit because you fucked up? Yeah, I can see resetting in that regard. You're challenging yourself because you enjoy a challenge when playing video games and you want to learn from your mistakes. You aren't punishing yourself to the point of frustration.

That's why I understand that some people desperately need that sense of accomplishment you can only get from brutally torturing yourself. People have fun with the challenge, even if it's to a point that other people would say is just absurd. But that goes both ways: if someone has fun with casual mode then more power to them. No one really have no right to say they're someone else is less of a player because they don't get the same thrill from violently torturing themselves as much as other players.

Still, I agree it's wrong for people to say "casual mode is the same as reset!classic" since, to put it bluntly, you're an asshole if you claim what you do is the same as what someone else does if they're putting in a lot more effort than you. Yeah, it's true that most people don't give a fuck if someone else has beaten the game on a higher difficulty, but people still need to be respectful enough to not belittle other people's accomplishments no matter how pointless they feel they are. That's just basic human decency. So... no, reset!classic is not the same as casual mode. The only way it comes close is if the player imposes a lot of restrictions on themselves, and even then they're only similiar at best, but never the same.