"What we have now is the bad kind of capitalism! There's a different, good kind of capitalism which in theory does all these great things!" is essentially the "communism works great in theory" argument.

100%, both systems are great theories. However, the last few hundred years of actually trying to implement capitalism has "most people have access to abundant food, cellphone in every pocket, access to a wealth of information, access to transportation, incredible medical advances.", if by "most people" you mean "possible a majority of people in the richest countries in the world". Unfortunately, the cost of that is that we've done irreparable damage to our environment, are causing the worst Great Extinction ever, and have caused a climate crisis that may cause us to go extinct.