In this fast-moving modern world, most people are looking for "fast" solutions. The same "fast" effect is expected by most people by taking pharmaceutical products.
Through thousands of years of Chinese medical history, tea has been recommended as a daily drink. The healing effect of tea is never a fast fix. However, the benefits of tea are shown clearly through months or even years. Eventually, you will notice a difference in your experience in comparison with others who have alternative drinks.
The first worldwide well-known tea book, The Classic of Tea (茶經), written in more than 1,260 years ago by Lu Yu (陸羽) in Tang Dynasty (唐朝), classified tea from farm to teacup, and health benefits from drinking tea in everyday life.
Modern academic studies found various healing benefits from drinking specific teas. For examples, "Theaflavin" was found to inhibit the coronavirus. Researchers experimented many teas, and they found "Theaflavin" would be available the most predominantly from native Taiwan tea tree. The leaves have to be processed into a fully-fermented red tea which has been proven to inhibit the coronavirus (Lung et al., 2020, Medical Virology, DOI: 10.1002/jmv.25761). I myself have been doing farm surveys and agricultural research for more than 15 years. In Taiwan, my research team investigated over 1,300 tea farms and farmers for Council of Agriculture granted project in 2016. The insight:
Only single origin tea, from a single farm with an in-house processing system, can be traced back to its origin. Only through this process of a growing and production method, can the tea provide substantial health benefits.
My opinion in regards to the health benefits of tea, for any blended tea across several farms, different regions, or even countries, it is almost impossible to trace or identify the plant. This also applies to the condition of soils. There are other environmental impacts such as the sun, rain and possible chemicals. Consequently, as these teas have no traceability, then my point of view on the health benefits would be the same. In other words, if you cannot trace them, you simply don't know how the tea was grown and processed. I would therefore challenge the health benefits of these teas.
Good tea enhances health, and heals the body physically and mentally. That's why tea ceremony, in any easy or complicated format, is a form of a meditation for the chaired person.