Requirement of different reagents for bromination of different substituted benzene rings

Question

Consider the bromination reactions of phenol and anisole. We know that the former can be brominated by aqueous bromine, while the latter requires the catalyst $\ce{FeBr3}$ instead.

Our teacher said that $\ce{-OH}$ is a stronger ring activator. So, polarization of bromine takes place easily and, hence, phenol doesn’t require a Lewis acid for bromination.

But, this related question had the conclusion that both anisole and phenol are practically equally activating. So, does aqueous bromine react with anisole too? If not, why is there a difference in the reagents? If yes, do we get 2,4,6-tribromomethoxybenzene?

We have a similar case with chlorobenzene also. Difference in electronegativity between $\ce{C-O}$ is more than that in $\ce{C-Cl}$. So, chlorine must be able to give one of its lone pairs and activate the ring more readily than oxygen. But even bromination of chlorobenze requires a Lewis acid. Why is this so?

PS: I checked this similar question on our site but a proper reason wasn’t stated to my question.

$\ce{-OH}$ is a better activator than $\ce{-OCH3}$ see this question — Avyansh Katiyar, Mar 30 '18 at 10:00
Possible duplicate of Why is a hydroxyl group more activating than a methoxy group in electrophilic aromatic substitution? — Archer, Mar 30 '18 at 10:04
The accepted answer says they both are practically equally reactive. — MollyCooL, Mar 30 '18 at 10:11
It might be true that $\ce{-OH}$ and $\ce{-OCH3}$ are about equally activating. But phenol in water is partially deprotonated, and $\ce{-O^-}$ is a great deal stronger than both. — Ivan Neretin, Mar 30 '18 at 11:11
Interesting! And phenoxide ion is stabilised by resonance. Thats a good reason. Thanks. — MollyCooL, Mar 30 '18 at 11:34
@IvanNeretin I was taught that phenoxide ion is only stable in basic medium. Can it also form and remain stable in neutral medium? — Gaurang Tandon, Mar 30 '18 at 11:36
@GaurangTandon "Stable" is a word that means nothing, so you may just as well stop using it. True, to deprotonate all phenol molecules we'd have to go into much higher pH. With neutral solution, at any given moment only a tiny portion of them is deprotonated. This is also the portion that reacts. Then they exchange protons, and we go on to brominate another portion. Then another. — Ivan Neretin, Mar 30 '18 at 11:41
@IvanNeretin Alright, makes sense. Still, your comment makes me feel that aqueous bromination of phenol will be a slow process. Is my interpretation correct? — Gaurang Tandon, Mar 30 '18 at 11:43
@GaurangTandon Not particularly. See, the portions may be tiny, but they exchange really fast, and each portion brominates pretty fast, too. — Ivan Neretin, Mar 30 '18 at 11:59
Phenol is easily brominated by bromine in water. The reaction hereby proceeds to 2,4,4,6-tetrabromocyclohexadienone. The reason for this is, as Ivan already explained, the presence of phenolate anions. The product can be reduced to 2,4,6-tribromophenole by sodiumhydrogensulphite. — aventurin, Mar 30 '18 at 12:21

Requirement of different reagents for bromination of different substituted benzene rings

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