AndOTP is not maintained since a while - https://forum.xda-developers.com/t/unmaintained-app-4-4-open-source-andotp-open-source-two-factor-authentication-for-android.3636993/page-6#post-87021655. It is nice indeed, but since it's about security I'd prefer something active to increase the probability to have all the fixes in time.

How does bitcoin support the transition to non-fossil fuel energy?

No, with Whirlpool using Samourai or Sparrow wallet you don't need to manage every coinjoin manually - you can start with whatever amount, then it is split into 100k (or larger if you prefer) chunks and they are mixed automatically then. You only have to keep the machine running the wallet turned on all the time. First mix happens very quickly, but if you want better anonymity for your UTXOs it's typical to wait for at least 3 mixes for each, and that can take quite a while (usually I had no more than 10 remixes per week, running 24/7).

I do coinjoin almost all bitcoins I buy in a way different from non-KYC p2p (never used a real KYC exchange, but some local exchange services that technically can track my identity easily if they want).

One important reason to do that is not just hide the history of your coins, but make your future counterpart be totally uncertain on how big your stack is. That's why I think it is important to use as small denomination as possible, e.g. 100k sats in Whirlpool. It is slow but worth that.

Withdrawal your money from an exchange using LN (and then swapping to onchain in small portions if you like) seems a bit worse but still acceptable option to me.

But it is not either guaranteed to be kept open forever by ACINQ, especially if all the inbound liquidity is on your side, if I understand correctly?

OK, probably true for an average user. Still it seems reasonable (just to me?) to assume that, say, 1% of people would want to maintain this self-sovereignity. And even those people - 80M (taking a likely wrong assumption that the world population saturates today) - will hardly afford a TX per year... I'm still not convinced it's the way to go.

well, here - primarily the personal control of one's own funds and not relying on any structures like those currently named banks. Of course we still keep some of the Bitcoin virtues even though (no inflation), but still

Does it not eliminate a major part of what we want to use Bitcoin for?

I was recently impressed by this one (source: https://www.reddit.com/r/Bitcoin/comments/13y0svg/halving_schedule_fib_spiral/):

A random guy whose posts I saw on Mastodon, who later disappeared from there so I can't really thank him anymore. I was already looking towards crypto before (due to certain infamous events in my country), though not strictly focusing on bitcoin. This guy just mentioned a few concepts such as lightning, multi-sig, whirlpool coinjoin, that triggered me to read more on that and eventually realized the power of bitcoin.