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Tested: Windows 11 Pro's On-By-Default Encryption Slows SSDs Up to 45%
(www.tomshardware.com)
This is a most excellent place for technology news and articles.
They don't slow down with encryption to any real degree.
Even before Apple added their dedicated T or M chips, they used the AES instruction set in Intel CPUs for hardware acceleration and the performance impact was within the margin of error (3%) https://archive.techarp.com/showarticle0037.html?artno=877&pgno=1