Macs probably would've been a reasonable choice for all the administrative/office tasks (emails, spreadsheets, presentations, all that jazz), leaving the heavy lifting to the IRIX boxen. Probably would've also been the typical first choice for GUI-driven applications (like NedryLand).
But I wasn't quite alive yet in 1991 (let alone administering IT deployments for biolabs and theme parks colocated on remote tropical islands), so what do I know lmao
Macintosh and SGI (+AIX, various Unix) were in fact a common combination used as desktop and backend server respectively in many 1990's scientific labs including biology labs.
The Jurassic park crew supposedly had a lot of money, and I would argue that any computer nerd, at the time depicted, would have gone with that combo. SGI for Unix and the power and Macs for admin. I would have.