I found out that it's possible to use the definite article "the" with adjectives, to refer to a group of people with a particular characteristic, e.g. the rich, the disabled, the poor, and so on.
But I don't know if it's always possible to use this pattern, or sometimes it doesn't sound natural, for instance:
When it's the first day of school, you'll find two types of people:
The shy that just want to be alone. And the talkative that are unbearable because they talk with each person.
JUST IN CASE: I also found that this pattern is common in legal contexts: The + adjective = replacing noun