Homebrew no detecta los últimos Xcode y Command Line Tools, y tampoco los desinstala

Tengo instalada la versión 10.14.5 de macOS Mojave con la versión 10.2.1 de Xcode y las herramientas de línea de comandos instaladas usando xcode-select --install . Todo el problema comenzó cuando intenté instalar youtube-dl fórmula en mi sistema ejecutando:

brew install youtube-dl

La salida que obtengo es:

Updating Homebrew...
Error: Your Xcode (1) is too outdated.
Please update to Xcode 9.0 (or delete it).
Xcode can be updated from
  https://developer.apple.com/download/more/

Error: Your Command Line Tools are too outdated.
Update them from Software Update in the App Store.

De nuevo, si ejecuto xcode-select --install me sale:

xcode-select: error: command line tools are already installed, use "Software Update" to install updates

Corriendo:

xcode-select -v

devuelve

xcode-select version 2354

(no sé qué significa esto) y corriendo:

xcode-select -p

produce

/Applications/Xcode.app/Contents/Developer

Debido a estos problemas, intenté desinstalar Homebrew (con el plan de reinstalarlo de nuevo) ejecutando el comando

ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/uninstall)"

pero da el siguiente error:

curl: (7) Failed to connect to raw.githubusercontent.com port 443: Operation timed out

A continuación, traté de desinstalar Homebrew utilizando el unbrew.rb script disponible en GitHub pero parece que no elimina Homebrew. He probado a ejecutarlo con y sin sudo. Incluso después de hacer esto, ejecutando brew config devoluciones:

HOMEBREW_VERSION: 1.3.2
ORIGIN: https://github.com/Homebrew/brew
HEAD: 751334a257d81851e68da7ab390982d4e9fdf909
Last commit: 1 year, 10 months ago
Core tap ORIGIN: https://github.com/Homebrew/homebrew-core
Core tap HEAD: 3fd7a855a1a357654a4a9a455162761841a4809d
Core tap last commit: 1 year, 10 months ago
HOMEBREW_PREFIX: /usr/local
HOMEBREW_REPOSITORY: /usr/local/Homebrew
HOMEBREW_CELLAR: /usr/local/Cellar
HOMEBREW_BOTTLE_DOMAIN: https://homebrew.bintray.com
CPU: quad-core 64-bit broadwell
Homebrew Ruby: 2.3.7 => /System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/bin/ruby
Clang: N/A
Git: 2.20.1 => /Applications/Xcode.app/Contents/Developer/usr/bin/git
Perl: /opt/local/bin/perl => /opt/local/bin/perl5.24
Python: /usr/bin/python
Ruby: /usr/bin/ruby => /System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/bin/ruby
Java: N/A
macOS: 10.14.5-x86_64
Xcode: 1 => /Applications/Xcode.app/Contents/Developer
CLT: N/A
X11: N/A
MacPorts/Fink: /opt/local/bin/port

Corriendo brew doctor produce lo siguiente:

Please note that these warnings are just used to help the Homebrew maintainers
with debugging if you file an issue. If everything you use Homebrew for is
working fine: please don't worry and just ignore them. Thanks!

Warning: Your Command Line Tools are too outdated.
Update them from Software Update in the App Store.

Error: Unrecognized Mach-O load command: 0x32

¿Se ha roto mi Homebrew por mis intentos de desinstalarlo? ¿Qué puedo hacer para reparar Homebrew y todos estos errores al señalar las herramientas correctas de Xcode y de línea de comandos?

He intentado actualizar Homebrew ejecutando brew update antes sin éxito. Corriendo:

brew update

devoluciones:

fatal: unable to access 'https://github.com/caskroom/homebrew-cask/': Failed to connect to github.com port 443: Operation timed out
fatal: unable to access 'https://github.com/Homebrew/brew/': Failed to connect to github.com port 443: Operation timed out
fatal: unable to access 'https://github.com/Homebrew/homebrew-core/': Failed to connect to github.com port 443: Operation timed out
Error: Fetching /usr/local/Homebrew/Library/Taps/homebrew/homebrew-core failed!
Fetching /usr/local/Homebrew failed!
Fetching /usr/local/Homebrew/Library/Taps/caskroom/homebrew-cask failed!