Everything the OP said is true. New street tires from the major producers don't need to be scrubbed. New race tires are not heat cycled and other than the warm-up lap, they hit turn one on sticker tires. Every heat cycle reduces the tire's grip, so race tires that have more than one heat cycle will be slower. Race tires are cooked in tire warmers for at least 30 minutes prior to taking the track, whether they are new or old.
Let people believe what they want. If they feel better scrubbing in tires so be it.
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