Makes sense I quess. But what about football coaches looking at their scouting reports or photos of the other team's alignments during a game? Wouldn't that be similar?
Fischer promotes a form of chess which requires random placement of the pieces at the beginning of the game rather than the recognized way in which the pieces are normally placed.
The "cheating" which this addresses is in the area of knowing the "opening book", that is, what sequences of opening moves lead to wins and which to losses.
Fifty years ago, this type of knowledge could only be obtained from actual books or from training coaches who had access to such books.
During this era Fischer was forced to compete against heavily coached and subsidized Soviet players. Despite this, he was able to do quite well because he is truly a chess genius.
In later years, computers became available but initially they were expensive and the chess database software was expensive. Without the resources to have such tools Fischer was even more disadvantaged when playing against subsidized opponents.
Now that computers and chess databases are much less expensive, there is less reason for a player to be without them. Nevertheless, Fischer supports the randomizing to eliminate the advantage of opening book preparation. The "cheating" which bothers Fischer is mainly the great assistance that is available prior to the beginning of a game, during adjourned games when specific positions can be studied in depth, and between games of a long match when specific lines of play can be subjected to in-depth analysis.
I tend to agree here. I don't approve of them sneaking off the to restroom though. Just because your opponent played a certain way 4 times before doesn't mean he'll do it the same this time. These are human players, not computers.