O Debian tem uma política bastante abrangente, por isso vale a pena referir-se a isso. Eu acho que isso cobre isso,
9.1.1 File System Structure
The location of all files and directories must comply with the Filesystem Hierarchy Standard (FHS), version 2.3, with the exceptions noted below, and except where doing so would violate other terms of Debian Policy.
E verificando FHS , encontramos
/usr/lib : Libraries for programming and packages
Purpose
/usr/lib includes object files, libraries, and internal binaries that are not intended to be executed directly by users or shell scripts. [22]
Applications may use a single subdirectory under /usr/lib. If an application uses a subdirectory, all architecture-dependent data exclusively used by the application must be placed within that subdirectory.
depois de volta à política do Debian,
The requirement for object files, internal binaries, and libraries, including libc.so.*, to be located directly under /lib{,32} and /usr/lib{,32} is amended, permitting files to instead be installed to /lib/triplet and /usr/lib/triplet, where triplet is the value returned by dpkg-architecture -qDEB_HOST_MULTIARCH for the architecture of the package. Packages may not install files to any triplet path other than the one matching the architecture of that package; for instance, an Architecture: amd64 package containing 32-bit x86 libraries may not install these libraries to /usr/lib/i386-linux-gnu. [69]
Applications may also use a single subdirectory under /usr/lib/triplet.
The execution time linker/loader, ld*, must still be made available in the existing location under /lib or /lib64 since this is part of the ELF ABI for the architecture.