I imagine they were developing this for some time, but launching a enterprise custody solution after the Liquid hack seems bold.

The solution integrates Thales’ hardware-backed security into the Blockstream Enterprise platform. The integration combines hardware-based key protection with a distributed approach to signing authority to provide elevated security benefits for institutional digital asset operations. 

Blockstream's approach allows Secure Multi-Party Computation (Secure-MPC), combining the distributed protection of MPC with the hardware-level security of Thales hardware security modules (HSMs). Unlike conventional MPC solutions, which may expose sensitive cryptographic operations to general-purpose computing environments, Blockstream's Secure-MPC executes the signing protocol entirely within the HSM's secure environment. This hardware-secured implementation of MPC ensures sensitive key material remains protected throughout the transaction lifecycle, including during signing, significantly reducing the risk of compromise and establishing a new standard for institutional digital asset custody.

To be fair, the Liquid hack didn't involve the compromise of any key material, so there's not really any reason to slight them on that count...but also, I don't think this solution would save them from a similar problem in the future.