Not sure if this briefly viral tweet was meant as serious advice. But I say, don't try this at home - unless you really want the lobster to be the main beneficiary of your wealth!
Here's why:
Nearly all states have essentially abolished the rule against perpetuities. So, absent some highly unusual circumstances, you shouldn't worry about it in planning your estate.
Lobsters aren't actually immortal! They die of natural causes all the time. This is the one part of this I didn't know based on my own expertise. But it was easy to look up.
Even if RAP was still in force and lobsters WERE immortal, creating a life estate for a lobster wouldn't actually help circumvent RAP. I could explain why. But trust me when I say that 1) I know what I'm talking about, and 2) you really don't want to know the reasoning here, unless you're a glutton for punishment.
On the plus side, if you really want to leave your property to a lobster, you most definitely can! You can create a trust with the lobster as beneficiary. People have done this for a variety of animals, including cats and dogs. But if you follow this route, the trustee will have a legal duty to actually use the property for the benefit of the lobster (e.g. - spend money on getting him better food, a better living environment, high-quality veterinary treatment, etc.). It can't be a clever way to actually let some human profit from the estate, under the guise of helping the lobster. A trustee who diverted the funds in that way would be acting illegally, and could face both civil and criminal liability.