The “phone filters” we still like to use are a throwback to Western Electric desk sets with carbon mike transmitters and metal diaphragm earpieces. This is the sound that we have come to expect when depicting the far side of a phone conversation. The landline phone system and hardware nowadays do sound just a little better than that, but we’re psychologically prepared to hear that tinny sound on film, video and radio.
What we really need to have is what suzin wants, a preset “cell phone sound” filter. Ideally(?) it would output voices a bit muffled, full of digital glitches, sampling errors and aliasing, occasional drops, and complete sentences scrambled and wrongly reassembled. Like in real life.