True for coffee and green tea.

UK taste insist black tea must be boiled. And that dose not mean 100c but diff temps at different altitude. Hence most of our kettles use the physics of boiling water. Rather then temp to turn off.

The effect of boiled water releases certain flavours in the tea. Those who like darker tea (more tanning released) tend to be the most fussy about this.

Tanning is also the chemical in tea that calms the mind. Hence why Brits have a tradition of turning to tea in stress etc. the tanning and caffeine work well together to clear allow a relaxed but active mind.