We all know the advantages of BTC, but what are some of the disadvantages??
Well one that i can think of is that it is still not perfectly anonymous. Personally i'd like to see bitcoin evolve into the future into something like XMR with essentially in built coin mixing. This is probably not necessary but rather an add on.
Another thing is that, fees are often high.
Also, blocks are 10 minutes on average in between so that means you're probably not going to be able to get stuff irl instantaneously without the merchant having to trust you.
one of the weaknesses of bitcoin, the lack of government control also makes bitcoin seem worthless. In addition, some financial observers consider bitcoin as illegal currency because it is not encouraged legislation lawful in the eyes of the law