Just like if you want heavy armor you get the problems associated with it as well as its AC. You want two handed weapons for damage, you dont use shield. You want fireball for aoe dmg, it's not the best choice inside some places.There seems to be a trend in the posts here, and it boils down to this:
Wherever there's a benefits-drawbacks trade-off, foreground the benefits and background the drawbacks.
Sorry, but that ain't how life works. Benefits and drawbacks go hand in hand, largely because the drawbacks are often there to either temper the benefits or make the choice to take them more difficult; and to take the benefits while in effect ignoring or backgrounding the drawbacks is, in a way, just another definition of cheating.
You want the benefits of having a tiger as your animal companion and co-warrior? Fine, but you'd better be ready to deal with the drawbacks that'll come if you ever try to take it into town.
You want the mechanical benefits of playing a Dragonborn (or Tiefling, or Drow...) instead of an Elf? Fine, but you'd better be ready to deal with the role-playing drawbacks of playing what is, in the eyes of most civilized inhabitants of the game world, a monster.
You want the benefits of playing a Paladin instead of a Fighter? Fine, but you'd better be ready to follow your Oath (or alignment, in earlier editions), make the required donations and to be faced with some very hard choices now and then; with said choices sometimes really p-ing off the rest of your party.
In short, if you can't handle the drawbacks don't try for the benefits.
Lan-"I think I'm in a minority of one on this, but for some reason I've always despised 'animal companions' for Druids and Rangers - familiars for casters are bad enough"-efan
DnD is full of cases where you make a choice, you get a mixed bag of plusses and minuses and then you do what you can.
Guess we should in some eyes have problem proof mounts, armor with no drawbacks, summoned companions that nobody reacts to and fireballs that only affect does, not friendlies or papers on desks we want...
Sounds oddly like a great many video games.
If that's someone's style that's great.
But it's not the premise dnd 5e was built on.
And it's ok for a gm to want to run a game that way without getting his decency questioned.