Important thing to note is, as men age, the amount of testosterone levels go down gradually and this can be seen once a man crosses his 30s. This drop should be gradual and in normal healthy circumstances, a man will be able to have sex even after 60 years of age. (Frequency varies by weeks or even months).
Recently, in the month of May 2022, a study funded by Cancer Research UK has presented a paper to the European Congress on Obesity in the Netherlands and it stated that after going through several research papers and examining 2.5 million (25 Lakhs) men, obese men are more likely to die from prostate cancer.
If you lost interest in sex after recovering from COVID-19 and if it has been over few months and you haven’t got your libido back, then, it could probably be a long covid symptom and you might be having Erectile Dysfunction as per the study published here.