Why does namei return an exclusively locked vnode when LOCKSHARED is specified?

According to namei(9), namei should return a shared lock when
LOCKSHARED is specified.  But in my experiments, it always seems to
return an exclusive lock instead.  For example:

$ cd /usr/tests/sys/fs/fusefs
$ sudo dtrace -i 'fbt:fusefs:fuse_vnop_getattr:entry /pid==$target/
{printf("islocked=%#x", args[0]->a_vp->v_vnlock->lk_lock); stack();}'
-i 'fbt:kernel:vop_stdstat:entry /pid==$target/
{printf("islocked=%#x", args[0]->a_vp->v_vnlock->lk_lock);}' -c
"./getattr --gtest_filter=Getattr.attr_cache -v"
[==========] Running 1 test from 1 test suite.
[----------] Global test environment set-up.
[----------] 1 test from Getattr
[ RUN      ] Getattr.attr_cache
INIT        ino= 0
ACCESS      ino= 1 mask=0x1
LOOKUP      ino= 1 some_file.txt
GETATTR     ino=42
[       OK ] Getattr.attr_cache (3 ms)
[----------] 1 test from Getattr (3 ms total)

[----------] Global test environment tear-down
[==========] 1 test from 1 test suite ran. (4 ms total)
[  PASSED  ] 1 test.
CPU     ID                    FUNCTION:NAME
  3  19743                vop_stdstat:entry islocked=0x21
  3  19743                vop_stdstat:entry islocked=0xfffff80004f16740
  3  68298          fuse_vnop_getattr:entry islocked=0xfffff80004f16740
              kernel`VOP_GETATTR_APV+0x90
              kernel`vop_stdstat+0x147
              kernel`VOP_STAT_APV+0x91
              kernel`kern_statat+0x183
              kernel`sys_fstatat+0x27
              kernel`amd64_syscall+0x1af
              kernel`0xffffffff8106cd5b

  3  19743                vop_stdstat:entry islocked=0xfffff80004f16740
  3  68298          fuse_vnop_getattr:entry islocked=0xfffff80004f16740
              kernel`VOP_GETATTR_APV+0x90
              kernel`vop_stdstat+0x147
              kernel`VOP_STAT_APV+0x91
              kernel`kern_statat+0x183
              kernel`sys_fstatat+0x27
              kernel`amd64_syscall+0x1af
              kernel`0xffffffff8106cd5b

dtrace: pid 3554 has exited

From that output, the first vop_stdstat is probably for the
mountpoint, and isn't what I'm concerned about.  But the second two
are for a fusefs file.  The LK_SHARE bit is not set, indicating an
exclusive lock.  That's even though the call to namei in kern_statat
specifies LOCKSHARED | LOCKLEAF.

What am I missing?