Yes, because that is the kind of character I want to play.
My character with an 8 strength and 15 int and 14 charisma is capable in melee. Better at ranged, but still good enough in melee.
Constitution is overated IMO and does not give you many more hps anyway.
Richard was a crussader and is the archetype for a Paladin which uses charisma as a core ability.
They can support combat with INT and CHA already. Any character can do this, regardless of class.
Unless your role is a spell caster, the characters "key role" is for the most part determined by the player, not by the class. If you want to play Faramir then invest in Charisma.
I think that is absolutely not true in real life and makes little sense in d&d world when you can have a 3 foot tall halfling woman deal 100 damage in melee.
I have seen plenty of "dumb jocks" in real life that are muscle bound and not intimidating at all and then other people like gang members, thugs and anyone with a gun that are small and very intimidating. I think being strong may play into it, but it is your ability to use that and leverage that during interaction and that is charisma. A muscle-bound buffon will not intimidate many people, while the mild mannered cold blooded killer will.
If you want strength(intimidation) the rules are there but in my games it is always charisma and the specific threat you use sets the DC. My fighter above with an 8 strength would have a high DC if she threatened to bash your skull in, but would probably have a lower DC if she cast minor illusion and showed the guy a picture of his house burning down with his wife in it. Either way she would use her 14 charisma.
Real in game example - she is a 5 foot tall teifling and we were interogating a prisoner. I used minor illusion make my face show a devilish visage and put glowing circles in front of my eyes. I told him I was putting a curse on him and if he lied he would be dragged to hell. Another character helped by casting prestigitation and making it hotter around him. I rolled an intimidation against a DC 10 with advantage. If I had threatened physical harm if he lied to us it would have been a much harder check. If the Barbarian (whos is strong) had threatened physical harm it would have been a lower DC than me threatening bodily harm, but probably not as low as I got it without some creativity on his part and then if he did not have the charisma he would not get the bonus.
Spellcasting and race aside I would think assassins would present the most fearsome demeanors as their art is killing people.