I really don’t understand why you’re arguing this. OP uses a 6 this long, asks to know if the 8 is worth it, likely to learn if it will serve him/her just as long or better. I point out the 8 will be relevant longer, which is obviously something that is pertinent to the OP’s needs. Suggesting anything other than an 8 (ignoring financial restrictions, which I also covered in my very first post) is foolish. There are many features outside the SOC alone.
I never suggested which device the OP should migrate to, only to offer input on the current 8. However, I think your conflating as you have been in the previous post(s). I'm not arguing what device the OP should use or upgrade to, I'm simply advising my original point from the beginning, is your idea of future proofing is a misconception and is its poorly used. I don't disagree that the iPhone 8 is a current standard today, but given the iPhone power management and and how somebody uses their iPhone, and when they actually upgrade, future proofing is irrelevant.
At this junction, any upgrade from iPhone 6 is an upgrade in general. But some might argue that iOS is a downfall with how it will perform internally with the iPhone. But none the less, I'm not necessarily trying to argue with you for the sake of who's right or wrong, it's more or less I don't believe you're appropriately using the term future proofing. I will say it again, future proofing is an overly exaggerated and misunderstood moniker that doesn't guarantee anything based on all the user tends to utilize the iPhones capabilities and features, and for what time length.