1. Bitcoin is not easily understood by people with no knowledge of it, at such scam and fraud is high on them.
People having a misconception about bitcoin is not a negative influence to me, they people has the lapse from their end in the lack of the ability to try out something new, take a risk and believe in what bitcoin has come to offer in the entire financial system and economy
2. No refund to anyone who incurs loss through keys, seed phase or fraud.
I can't accept this is well as a demerit to bitcoin becau if you're been careless with your fiat currency abd lost to due to vulnerability or attack it's all gone for life, same applies to bitcoin, you can make a mistake and expect it to be reversible or undo when you're at fault and not the blockchain technology.
3. Privacy- bad people trying to give bitcoin bad name by faking bitcoin apps and site.
The more reasons to avoid storage of your asset on centralized exchanges, or believe all those crypto influencers and some crypto projects, NFTs and their likes, the bad ones are many than the few good ones.
4. Cyber hacking - cyber wizards an fraudsters makes people to loss bitcoin wallets and money.
The problem here is not bitcoin but you for using a centralized exchange and been careless with your wallet security and private keys.