Android Studio for Mac download error
As others have suggested in comments, it could possibly a network/Internet configuration issue. You can try the following in addition to tweaking network settings or switching to a different one.
If you have Homebrew installed on your Mac, try downloading and installing it using the following command:
brew cask install android-studio

If you do not have it installed, you can follow the instructions on Homebrew homepage to install and set it up and then you can run the above command.
If you do not wish to install Homebrew, you can use the following link to download the Android Studio DMG:

https://dl.google.com/dl/android/studio/install/4.0.1.0/android-studio-ide-193.6626763-mac.dmg

You can either download the link using a web browser or a download manager of your choice. You can also use the macOS built in curl command to download the DMG by running the following in Terminal:
curl -O https://dl.google.com/dl/android/studio/install/4.0.1.0/android-studio-ide-193.6626763-mac.dmg


P.S.: The hyperlink in this answer is different from the one used when downloading directly from the website. Both the links are from official source and should lead you to download the exact same version of Android Studio at any given point of time.