Kinda off topic here but still semi-related to hypercars, but here's how I see it (for cars weighing less than 4k-lb):
Supercar— ¼mile at 115-129mph in 12 to 13sec — usually starting price (before taxes and fees) was US$100,000—399,995
Here you have cars like Porsche 959, Ferrari GTO and F40 and F50, Bugatti EB110 GT, Lamborghini Diablo, Cizeta V16T, Porsche 993 GT2, and Vector W8TT. To an extent, some Euro-spec 360 Modena and US-spec Viper GTS press cars as well.
Hypercar— ¼mile at 130+mph in less than 12sec — usually starting price (before taxes and fees) was US$400,000+
Here you have cars like Euro-spec F40 without cats, McLaren F1 (all versions), Bugatti EB110 SS, Dauer 962 Le Mans, Jaguar XJ220 S. In addition: Porsche 911 GT1 (993/996), Mercedes-Benz CLK GTR, and any of those other dangerous GT1 prep cars.
Supercar— ¼mile at 120-134mph in 11 to 12sec — usually starting price (before taxes and fees) was US$150,000—599,995
Here you have cars like Porsche GT2 (996/997) and Carrera GT, Ferrari 430/458 and Enzo, Ford GT, Corvette Z06 and ZR1, Viper SRT-10, SLR McLaren, Audi R8 V10, Lamborghini Gallardo (some versions) and Murciélago, Mosler MT900, naturally aspirated Saleen S7, Koenigsegg CC8S, and a few others I forgot to mention.
Grand tourers may include Mercedes-AMG SL65, Ferrari 599, and Porsche 997 Turbo S.
Those in the last two years of the 2001-12 era of the supercar segment include Aventador, F12, and MP4-12C; but barely out of hypercar reach.
Hypercar— ¼mile at 135+mph in less than 11sec — usually starting price (before taxes and fees) was US$600,000+
Here you have Saleen S7TT, Koenigsegg CCR (and updated version CCX), Bugatti Veyron, and to a lesser extent Ferrari Enzo (which honestly plays in both segments). Even McLaren F1 and Dauer 962LM from the '90s would still be qualified to play in this league.
Supercar— ¼mile at 130-144mph in 10 to 11sec — usually starting price (before taxes and fees) was US$200,000—799,995
Hypercar— ¼mile at 145+mph in less than 10sec — usually starting price (before taxes and fees) was US$800,000+
Supercar— ¼mile at 135-149mph in 10 to 11sec — usually starting price (before taxes and fees) is US$200,000—799,995
Hypercar— ¼mile at 150+mph in less than 10sec — usually starting price (before taxes and fees) is US$800,000+
For cars weighing more than 4000 pounds, you must take dynamics into account. Sure, a standard Chiron or an electric car launches like a hypercar, but neither will ever outperform a lightweight track monster on a circuit.
This is why cars like the Viper ACR, Senna, and GT2 RS are often faster than supercars and even some hypercars on the track. This is why a Hellcat won't actually beat its supposed Chevy, Cadillac and Ford rivals on a track, because dynamics aren't taken into account; too much focus on horsepower; basically a budget Bugatti.
I went by US presidential (both campaign and incumbency) years, so 1984-2000 -> 2001-2012 -> 2013-2020 -> 2021-present.
Back then, Corvette ZR1 (C4) and 911 Turbo (964/993) weren't considered as "supercars." These days however the ZR1 and Turbo S (and even smaller siblings like Z06, GT3, and Turbo) are supercars because Chevy and Porsche accidentally caught up with their naturally-exotic rivals.
NOTE: I would consider some of those Ultras and Radicals and the like to be kit cars.