Apparently TeX Live 2017 is now in the freeze period in anticipation of Tex Live 2018, because I tried running sudo tlmgr install tikz (for a re-install of TeX Live I was doing), and I hit this error:
TeX Live 2017 is frozen forever and will no
longer be updated. This happens in preparation for a new release.
If you're interested in helping to pretest the new release (when
pretests are available), please read http://tug.org/texlive/pretest.html.
Otherwise, just wait, and the new release will be ready in due time.
tlmgr: package repository http://ctan.mirrors.hoobly.com/systems/texlive/tlnet (verified)
tlmgr: saving backups to /usr/local/texlive/2017/tlpkg/backups
tlmgr: no updates available
Given I don't have the time to wait until whenever TeX Live 2018 releases to install tikz, is there a way to circumvent the freeze, or will I have to manually install packages from CTAN?
tlmgr update --all; if you issuetlmgr install <package>you will get the warning of TeX LIve being frozen, but<package>will be installed, if not yet present on your distribution. – egreg Apr 02 '18 at 09:42