1. orphans happen often but you dont see blockstream orgasming when those orphans are based on bad core code
This is not an orphan. An orphan is a valid block. This block is invalid, entirely different from an orphan. An orphan can lead to a valid chain which EVERYONE will follow. This block is invalid, and can lead to a chain where SOME NODES (not all nodes) follow.
When has a miner running just Bitcoin Core as their node (and thus not SPV mining) mined an invalid block?
2. the block got rejectct in 3 seconds .. end of drama..
3 seconds in which an SPV miner could have found a block on top of the invalid one and thereby causing a chain split.
but core nodes were set to ban nodes in such an event (over dramatics)
Rejecting a block for being invalid and subsequently banning the node that sent the block is not behavior just limited to Bitcoin Core. It is present in Bitcoin Unlimited as well and any other software derived from Core. Such behavior has been in the code for a very long time.
3. this block reject, like other oprhans proves that consensus and orphans work
Again, this block was invalid and rejected. It is not an orphan. They are two very different things.
4. this proves that altcoins are not created just due to a slightly larger block
5. this proves that all the core rhetorical and scripted doomsdays are wrong.
This just shows that it will not always happen. This does not mean that it can't happen.