No? Any modern disk encryption system with a strong passphrase (basically, anything but default-BitLocker) is very effective against "they have your physical machine and it's off" for any known, current adversary. And, the basic cryptography in use is common, robust, and proven enough that this is probably true even if your tinfoil hat is balled quite tightly.

Where modern research effort goes is into protecting against "they HAD your physical machine and they gave it back to you" or "they got your machine while it was on/running" - these are much more difficult problems to solve, and are where TEE, TPM, Secure Boot, memory encryption, DMA hardening, etc. come into play.