Fwiw, the national average drop in time due to shoes, social media, and the Internet is only about 2-3 seconds.
Here are the 250th best 1600 times by year.
2024 4:16 (season ending peak races still to come)
2023 4:13.99
2022 4:14.2
2021 4:15.9
2020 4:27.8
2019 4:17.0
2018 4:16.7
2017 4:16.7
2015 4:16.5
Times earlier are higher, but I question whether they are as exhaustive.