Neither .bashrc nor .profile gets read when bash is set as the shell in macOS 11

I know macOS 11 is trying hard to convince me to use zsh, but it also says I can choose another shell, which I have: chsh -s /bin/bash. The problem is, it no longer works as it did, as it neither reads my .profile nor my .bashrc when I start Terminal.app or iTerm.app. I just get this:

The default interactive shell is now zsh.
To update your account to use zsh, please run `chsh -s /bin/zsh`.
For more details, please visit https://support.apple.com/kb/HT208050.
bash-3.2$

If I now manually type bash, things happen as they should:

bash-3.2$ bash
[Timer is unset. Use timer_start] core utils setup finished
[3] Executing $HOME/.bashrc
[7] Reading utility functions and aliases
[10] core utils setup finished
[14] Reading aliases and functions
[22] ssh aliases
[26] conversions
[30] Use htop if available
[36] small utils and aliases
[40] aliases: setting up node aliases
[44] aliases: finished setting up node aliases
[48] webserver aliases
[52] global aliases and functions finished
[56] Reading utils for git prompt
[63] Reading bash completion files
[69] /Users/carlerik/.bash_completion.d/azure
[75] /Users/carlerik/.bash_completion.d/git
[89] /Users/carlerik/.bash_completion.d/npm
[95] /Users/carlerik/.bash_completion.d/tmux
[100] Reading color codes
[105] Read /Users/carlerik/.bash.d/colors
[130] Read /Users/carlerik/bin/z.sh
[135] Reading local settings for this machine
[140] Load personalized bashrc for mac
[152] Read /Users/carlerik/.bashrc.local
This setup is missing 'direnv'. Please install it for per-directory overrides
[157] Finished bash setup
[205] Read /Users/carlerik/.secret

The default interactive shell is now zsh.
To update your account to use zsh, please run `chsh -s /bin/zsh`.
For more details, please visit https://support.apple.com/kb/HT208050.

carlerik at idas-imac in ~
$

All the timing stuff is due to a DEBUG setting I have enabled (my .bashrc in my dotfiles). So it works as normal.

How can I get macOS 11 to use my .bashrc and/or .profile on startup?

I have even tried overriding the terminal settings in both apps from the standard logon shell to /bin/bash --rcfile $HOME/.bashrc with no further success (just as a temporary workaround to see if it was possible to force it to read my init files).

For reference, this is my .profile:

printf "Reading .profile"
export DEBUG=1

if [ -n "$BASH_VERSION" ]; then
    # include .bashrc if it exists
    if [ -f "$HOME/.bashrc" ]; then
        . "$HOME/.bashrc"
    fi
fi

# other stuff
# ...
# other stuff end

if [ -f "$HOME/.profile.local" ]; then
    . "$HOME/.profile.local"
fi

The answer to this was hinted to by @mmmmmm: without my knowledge, a .bash_profile file had been added, thus making bash choose to read that instead of .profile.

The culprit was the installer script for gcloud, the CLI for the Google Cloud SDK.

For my cross-platform dotfiles, I have moved these mac-specific settings to another file which is only read when using mac (in my setup).