You’re absolutely right that…
You’re absolutely right that different batteries have different recommendations, and the changes Tesla made to their charge guidelines are probably influenced by a mix of caution and a desire to protect their reputation. It’s interesting to consider the impact of battery architecture and materials—some batteries are just more resilient to higher charging levels than others. I agree with your point about the 6-8 year window. If you're not pushing the battery to its limits constantly, whether you charge to 80% or 90% is probably not a huge concern in the grand scheme of things. As for charging every day, it does seem to be more about convenience for most people, but I totally get the hesitation around doing it every day. Ultimately, the automakers have tons of data, so I guess they know what’s best for the long-term health of the battery!