That's not what letter of the law prescribes in this case. There is literally no constitutional guidance about what merits removal. It's intentionally left vague and subject to congress's judgement. The fact that you think Clinton definitely deserves removal and Trump doesn't confirms my position that presidents are treated unfairly by the opposition.
You don't have to say "all" to make a generalization. He made a generalization. If I said "Christians are idiots", I can't then say "I didn't say 'all', so I'm not a bigot." It's a bigoted thing to say whether you say "all" or not.
When we talk about who is racist, it's definitely a matter of opinion. You're trying to argue semantics to say it's an objective thing, but even if there is one clear, universal definition of racist, it's still subjective when we decide who is racist and who isn't.