Yeah it's loosely based on The Tempest, with Dr Morbius taking the place of Prospero and Alta being the stand in for Miranda, suddenly having to play host to a visiting band of strangers, with the monster being a latter day interpretation of Caliban
MGM Studios was well known for their musicals like Singing in the Rain and such.
When you saw an MGM musical, you knew that they put the money and talent into them.
When they wanted to do a SciFi, the same thought was there.
Although Earth vs The Flying Saucers was the top grossing film of the same year, Forbidden Planet just about broke even.
But they took the movie seriously and relied on you to use some imagination in picturing the Krell or what their world looked like.
The explorations of psychological monsters and enlightened societies as well as portraying the first starship to travel faster than light, all contributed to a more esoteric film for that time.
It still stands today…more of a work of art than just lasers and spaceships.
It set the bar for serious film makers to strive to have better looking effects in each successive decade, Space Odyssey and 1977s Star Wars being the result.
Practical effects gave way to the economics of cgi but they are making a sort of come back from time to time.
One take away from Forbidden Planet to Star Trek was that Gene Roddenberry wanted similar uniforms even with the military style hats.
Having served in the Second World War, he wanted that regimented quality but gave way to a more relaxed, quasi military feel, instead.
But the hats and uniforms did make it into the 2009 reboot.
Not much bare feet after Anne Francis’ frolicking, though.