That is true, but as a speaker of foreign languages, we have to recognize that Italian, as well as other languages, are easier to learn if we think in their syntax. "He wants you to eat an apple" is literally "Ti vuole mangiare una mela" but that doesn't translate well. If "He wants that you eat an apple" sounds like old-english, then Italian will be easier to learn if you think in old-english.
No, you only use the infinitive if it's the same subject wanting to do the action. "Voglio mangiare una mela" - I want to eat the apple. If it's one subject wanting another subject to do the action, you have to use che, and "mangi" here is actually the subjunctive form of the verb mangiare. Vuole che tu mangi una mela. He wants (one subject) that you (other subject) eat an apple.
Modern English doesn't make it clear that it's one subject wanting another subject to do something (He wants you to eat the apple), so it's understandable why one would naturally want to use the infinitive.