Here is only one such brutal squeeze: registered security brokers must maintain control of all securities [0]. In practice, this means brokers use custodians[1]. Regulators have been working on making holding crypto harder for custodians [2].

[0]: Securities Exchange Act of 1934, Rule 15c3-3

[1]: https://www.sec.gov/news/public-statement/joint-staff-statem...

[2]: https://www.risk.net/investing/7956492/crypto-custody-faces-...