Can people stop posting this damn meme?

The 787b was already going to be banned from WSC competition after 1990. The World Sportscar Championship, which held the 24 Hours of Le Mans at the time, had went to a 3.5L N/A formula starting in 1991 in order to “get F1 engines into the WSC”, of if you’re a cynic, the other way around.
In 1990, the 787, the previous year’s evolution of the car and Mazda’s first attempt at a car eligible for C1 entry performed very disappointingly at the 24 Hours of Le Mans, with both 787s qualifying below 20th place overall, neither of the 787s finishing, and the 787’s predecessor, the lower-class 767, finishing 20th overall.
Leading up to 1991, all ex-C1 cars that would not comply with the new regulations were going to be grandfathered into the C2 class for 1991 only. This meant that cars such as the Sauber-Mercedes C11, Jaguar XJR-12, Porsche 962, and yes the Mazda 787b would no longer be racing at the 24 Hours of Le Mans after 1991. Oreca, (the same Oreca which built the Chrysler Viper GTS-Rs, the spec LMP3 engine, the 03 and 05 LMP2 series, and ran factory programs for Toyota and Chrysler), who ran the Mazda program at the time, convinced the ACO that the 787b would be extremely hampered by the C2 regulations, and that the 787b deserved a weight break of 170 kg, down from the class-mandated 1000kg. Even then, it wasn’t the fastest of the 787s qualifying with the 12th-fastest time, and winning due to a late-race reliability issue with the leading Mercedes. To add to that, in the three championships the Mazda competed with, the Mazda finished fourth (JSPC 1990), fourth (JSPC 1991), and fifth (WSC 1991) in the manufacturer’s standings.

As far as Le Mans goes, the 787B was not the last car to compete at Le Mans, . Rotary engines with a swept volume of 3.4 liters were written into the ACO LMP2/LMP675 regulations up until the end of 2010.
1994 saw Mazda finish second in the GTO class at Le Mans and the mid-late 90’s saw Mazda-blessed Kudzu chassis earn class podiums at Le Mans.
In 2002, AutoExe campaigned a R26B-powered WR LM2001 in the LMP675 class, with the car DNFing after 5 laps in the 24 Hours of Le Mans. In 2006, B-K Racing, with factory Mazda blessing, campaigned in the ALMS with a Courage C65 2-liter 3-rotor engine, with little success. Bothe the WR-Mazda and the Courage faced similar issues of reliability and weight concerns caused by the dimensions and required cooling capacity of the rotary engine.