If the whole Bitcoin ecosystem forks, who you gonna send old fork coins to?
I think when you move your coins to a non forked system, they are now lost.
Any new coins you get on the old fork will not be usable in the new fork. That would be a new ledger that isn't compatible.
This understanding is wrong.
Let's classify the Bitcoin of today as chain A. If we fork we will have a Bitcoin B (new chain) and Bitcoin C (old chain - classified as A, when it was the only one). 2 different ledgers will be created from 1. Now when it comes to Bitcoin holdings:
If you had 5 Bitcoin on chain A, now you would have 5 on both chain B and chain C.
I think when you move your coins to a non forked system, they are now lost.
You don't send coins from chain B to chain C. That won't work.
But you are wrong I risk nothing by staying on the old chain its only those who fork that risk anything.
If the majority of the hash power switches away from the chain you are on, then that chain will stall as the difficulty is very high. It is certainly not risk free.
That's one of the dangers. Eventually it would stabilize and return to appropriate levels, although I don't think that chain would survive that long.