So, I probably should explain this, because there’s multiple levels to this joke.
The first level is the 2038 problem, when the “traditional” 32-bit signed time_t rolls over which is going to cause at least as much chaos as Y2K prior to 2000.
The second level is that Solaris has been 64-bit capable since the release of Solaris 7 in 1998, and 64-bit only since Solaris 11 in 2011, so it shouldn’t be a problem anyway.
The third level is the “Solaris Binary Guarantee” which states that a binary compiled for previous versions of Solaris will run unmodified on future versions. However, this means that binaries compiled for Solaris 10 and earlier may be 32-bit, using 32-bit time_t.
So, yes, but no, but yes. Maybe.