The only thing about SYSFS that is deprecated AFAIK is in init/Kconfig:
config SYSFS_DEPRECATED_V2
bool "enable deprecated sysfs features to support old userspace tools"
depends on SYSFS
default n
select SYSFS_DEPRECATED
help
This option switches the layout of sysfs to the deprecated
version. Do not use it on recent distributions.
HTH.
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