386: tailscale_1.46.0_386.tgz
amd64: tailscale_1.46.0_amd64.tgz
arm: tailscale_1.46.0_arm.tgz
arm64: tailscale_1.44.2_arm64.tgz
geode: tailscale_1.46.0_geode.tgz
mips: tailscale_1.46.0_mips.tgz
mips64: tailscale_1.46.0_mips64.tgz
mips64le: tailscale_1.46.0_mips64le.tgz
mipsle: tailscale_1.46.0_mipsle.tgz
riscv64: tailscale_1.46.0_riscv64.tgz

my devices are arm64, and based on your script will got 1.46.0 not found, it's should be 1.44.2. add checking for different architectures,
e.g wget -O- https://pkgs.tailscale.com/stable/ | grep -o 'tailscale_[0-9.]*_arm64.tgz' | grep -o '[0-9.]*' | head -n 1 will get 1.44.2, hopefully you are updating this. thank you very much