Even if that was no longer the case and SCOTUS were to overturn its own ruling in Hodges v. Obergefell, returning the marriage to the States, it is worth noting that:
1. at the federal level, same-sex marriage will still be recognized (along with its benefits, such as immigration) as long as the marriage is recognized in the state where it took place. The ruling at stake is not Obergefell but U.S. v. Windsor that repealed DOMA Section 3.
2. the Respect for Marriage Act passed by Congress ensured that a marriage valid in one state must be recognized in another state (even if that state were to no longer recognize same-sex marriage), and furthermore officially repealed DOMA Section 3.
In summary, from a pure legal standpoint, immigration benefits linked to same-sex marriage is not likely to change any time soon. But under the current administration, you are never safe from some surprises, depending on how the Department of Justice will instruct the agencies to enforce/implement/interprete the laws.