I think as DM you have quite some control over this.
Dodge is useful when players know who is going to get attacked.
So what if PC A, who is the tank, shouts out a provocation and then uses the Dodge action? If you as DM would make all the monsters attack PC A, then it's very useful and players will make more use of it. If you instead make your monsters attack all PCs except PC A because he took the Dodge action and it would be strategically better to attack the others, then your players will stop using Dodge except for very rare occasions where PC A would be at risk of immediate death if hit.
It can get a bit problematic, especially around feats like Sentinel. One approach is to let the dice decide. For example, in the case where a character wants to implicitly shape the behaviour of hostile creatures, I might rule that they need to make a Charisma (Deception) check, against those creatures' passive Wisdom (Insight) scores. Likely with
disadvantage as I assume that creatures experienced in battle, whose lives depend on it, and that are hostile to characters, will be unreceptive to attempts to change their behaviour.
Of course, failure in such a Contest means that the situation stays as it was, putting the problem back onto me to decide who a foe should attack. A heuristic that has emerged for me is something like -
1. Each side wants to remove the gravest threats from combat first
2. Experienced foes know that Barbarian ragers, and heavily armored fighters, are hard to take down, especially when they are dodging
3. Any foe can guess that the arcanist in a dress is easier to hit than the Eldritch Knight
4. Foes aren't psychic: they don't automatically know a character's abilities, but they do have eyes...
5. Experienced foes have heard of and even encountered things like Bladesong, Shield spell, rager resistance, the stance of a Sentinel...
6. Creatures in a world with spells, knows what it entails when a caster is concentrating, unless there is something stopping that like the spell was shaped by Sorcerer metamagic
The priority targets are usually the casters. They're often easiest to hit, and almost always pose grave danger. Occasionally it goes wrong, and foes end up dog-piling the fighter. I put weight on a foe's
experience, and assume the world is violent enough that any creatures who survived at all, did so because they are wily.
Sometimes I roll a die to decide. Other times, a foe faced with a dancing opponent and no good target, will just retreat. One DM we had would have them shut doors behind them in the dungeon: that was confounding.
Does this make dodge bad? I don't think so: I firmly disagree, based on my experience in play, with any humphing and saying it is pointless dodging because the DM will just have the foe attack someone else. The point of dodging is to shape the fight. In turn one, a dodge is very often a good idea, if one cannot close in one move. A caster with a clutch buff darned well should be dodging.
I think if the huge armored tank is dodging, then they should expect creatures not to attack them. That does not stop dodge being useful, just because the DM chose to never have foes break themselves on the bastion of the dodging Eldritch Knight. I guess I am saying that consistency - even consistency in refusing to attack the dodging tank - is information players can use to shape the fight.