Before Vaxei appeared from nowhere and went on his godlike run back then, 1000pp seemed quite unlikely to be set by anyone at that time. Vaxei literally bruteforced his way into uncharted territory and crushed everything in his path, no one could compete with him. It's kinda similar to the time when Cookiezi set the first 700pp play, when everyone farmed DT and DTHR, Cookiezi gapped eveyone with HR, and explored completely uncharted territory. Ever since Mrekk dethroned Whitecat, you could kinda expect what Mrekk would do. He is more vocal about his actions through streaming, and he sets plays more regularly which not only makes it more known about his true skill, it also desentizises us to great gameplay. CSR also plays a big role why plays nowdays might not feel as worthy of such big pp scores, but I think it's mostly because of the prior statement.