I actually thought viruses lived forever, but I was wrong. The paper linked in this article says 1 day on cardboard, 3 days on plastic.
I think it's more complicated than that. There are viruses that are enveloped in a membrane, and ones that are not. Unenveloped viruses can survive much longer on surfaces. IIRC, Covid-19 is an enveloped virus.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4462923/:
> Non-enveloped viruses, such as coxsackieviruses, rotavirus, or poliovirus, can survive for extended periods on surfaces (9, 10), while enveloped viruses, including H1N1 and human coronaviruses, remain infectious on surfaces after several days (6).
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1564025/:
> Most viruses from the respiratory tract, such as corona, coxsackie, influenza, SARS or rhino virus, can persist on surfaces for a few days. Viruses from the gastrointestinal tract, such as astrovirus, HAV, polio- or rota virus, persist for approximately 2 months. Blood-borne viruses, such as HBV or HIV, can persist for more than one week. Herpes viruses, such as CMV or HSV type 1 and 2, have been shown to persist from only a few hours up to 7 days.