Blue light filters have a purpose, but it isn’t eye strain. That’s just marketing bullshit from people who don’t know it’s purpose or can’t be bothered to translate it to laymen.
It’s purpose is to protect your retina from damage that accumulates throughout your life. It’s to protect you from developing macular degeneration. It does nothing anyone will notice, it’s more like sunblock, except you can’t feel the burn.
Also if someone sells you shit products, go to someone better if possible. But avoid chains at all costs.