Which package manager are you thinking of?
The dpkg ecosystem (i.e. Debian and Ubuntu etc.) definitely uses sonames. It is true that the soname version ends up in the package name, but this happens automatically, at build time, and it's only the binary package name that carries the soname, the source package remains unchanged.
You can install[] packages with libxyz.1.so and libxyz.2.so; you cannot install two -devel packages, because that package contains symlink libxyz.so to specific version.
Often, the system even installs such packages for you (they have compat in package filename, i.e. compat-libstdc++).
[] provided they don't contain additional files with assets, that conflict with each other. But this problem is not solved by gobo either.
