You can, Homekit call it "Adaptive Lighting". It's not as flexible though, you just turn it on and Apple does what it wants - there's no variables you can fiddle with if you don't like what its doing.
You honestly don't need one in the UK, filing small claims via the governments site is very easy. They'll auto send a demand letter for you etc. https://www.gov.uk/make-court-claim-for-money
Edit: Removed initial comment, confused my iOS faults.
Keychain its current configuration is risky, given its coupled to your iPhone password which many people frequently enter in a public setting. One shoulder surf followed by a phone theft and they've unlocked everything - including your iCloud account (which you can change the password on using iPhone password only).
If I go to system settings > password on iOS, it then requires Face ID to get in. So I’m not sure what you’re talking about. Under Face ID & passcode you can also require Face ID for a password auto fill. So I don’t think any of this is correct.
Are you sure? I always have to scan Face ID, whether it's to open the "Passwords"-section in Settings or to have it automatically paste a password on a website/app. How do I access these things without additional authentication?
I disabled that as it has some very confusing and undesired behaviour. For example if you're listening to Spotify on your Mac, then get a call on your iPhone you hit pause on your keyboard media keys so you can pick up the call - and it hangs up.
Where do you find places with specific lenses? Basically nowhere in the UK seems to call out their lense quality from what I've seen - perhaps I'm just looking in the wrong places. Are you ringing each optician up individually and asking them?
The branded lenses are often expensive and therefore high margin, so most opticians will have them available, but few people order them so they are unlikely to mention their existence. As to which are best, you are best finding an independent local optician who seems to have an interest in the subject and asking for a recommendation. If you read the Optiboard forums you can get an idea of the passion some opticians have, although it's not useful for specifics.
I don't know unfortunately - I just happen to have used an optician for years since buying my first set of glasses (Schuller Opticians in London) with just two branches, who uses Zeiss.