Amplified phones are an assistive technology that can help many more than persons who are hard of hearing.
I have a cheap plastic phone -- no speaker, no caller ID. It still works, so inertia prevents me from replacing it.
I only hear it ring if I'm at my computer table where it sits. I often struggle to decipher recorded conversations.
Amplified phones address all such issues. They can ring up to 95 dB, they make voices louder at both ends, have full duplex speakers, and usually talking caller ID.
Other common features, including keypads with large, illuminated numbers and visual ringers and message indicators can also make phone use easier for persons who are visually impaired.
Hearing phone calls, whether in a noisy office or living room, challenges most of us at some point.
I now know how to meet those challenges.