bitcoin will never ever go up again
the reasons are:
1. technologically outdated, there are better and faster tech basis available, why by bitcoin when its price rise nimbus and hype is gone, and its tech is outdated? do people still buy iphone 1s or old mobile phone?
Bitcoin is a work in progress. While I agree that it's currently outdated, things are being done on that front to address that. The next upgrade comes in the form of the Lightning Network, which aims to be just as fast, if not even faster, than the current available options.
2. still high costs.
You can send 5 sats/byte transactions again, so I don't know what you're talking about. Blame your exchange if this is the case with you.
3. slow.
If you pay a substantial fee (which is much lower at the moment), I can guarantee you your transaction will be confirmed in one or two blocks. Bitcoin is either slow or expensive, but rarely both.
3. propagandistic competition, there are more than 1500 coins now, that challenge communist rule via central banks, the original small bitcoin community is gone an entire new decentral financial market is now in existance
This could be true, but if we're using price as the basis, it doesn't hold water at the moment, and everything else is doing equally bad.