Thanks, it is sometimes hard to intuit a person’s emotions from text online.
Yes, this is indeed the reason for there being the two types of forks “soft” and “hard”.
In a soft fork, you create new rules which are also valid according to the old rules. So imagine the old rule was “only mammals allowed”. The new rules could be “only dogs allowed”. Since dogs are mammals, that means any blocks which conform to the new rules and are part of the heaviest chain (the one with the most accumulated POW), will be accepted by all nodes, whether or not those nodes were updated to enforce the new rules.
Now assume this “mammals” vs “dogs” scenario is a contentious debate, and there is not broad consensus among miners right out of the gate. Say there are some miners who are really passionate about mining “cats”, and they do not want to change. When the soft fork activates, some miners will adhere to the new “dogs only” rules, and a chain split will emerge as soon as one of those other miners includes a “cat”. Cats are mammals, so they would be allowed on the “mammals only” chain, but not allowed on the “dogs only” chain.
At this point, these two sides of the chain split will start accumulating POW independently. If the “dogs only” chain accumulates more POW than the chain with “cats”, it will wipe out the opposing chain, and Bitcoin would continue from that point onward under the “dogs only” rules.
On the other hand, if the “mammals only” side of the chain maintains the majority of the POW, it will grow to a point where the “dogs only” chain has no path to ever catch up, and activity on the “dogs only” chain will rapidly become unusable (for multiple reasons, such as the hash rate dropping too quickly for the difficulty adjustment to compensate making it impossible to mine, replay attacks, etc.). At some point they will have to give up, either due to the financial cost of continuing to mine a frozen chain, or to change the consensus rules yet again to turn their failed chain into a hard fork (like adding replay protection rules, etc) so that it can continue to live on (into obscurity) as a separate coin.
Now let’s walk through a similar exercise for a hard fork. Let’s say the old rules are “mammals only”, and the new rules are “birds only”. Now these are mutually exclusive (anyone who mines a dog will be rejected by everyone who is mining “birds only”, and anyone who mines a chicken will be rejected by everyone who is mining “mammals only”). Furthermore, all historic nodes (since they are running the “mammals only” rules) will reject all “birds only” blocks right out of the gate. Only users who actively update their node software to “birds only” will be able to participate in the hard fork. Because the two rule sets are mutually exclusive and have no overlap, there is no chance of one wiping out the other, and both can continue indefinitely on their divergent paths.