If you don’t like it, build your own stock market.
E.g. Asgardia can be considered a surprisingly successful proto-nation. AFAIK UN actually contacted them and asked to launch a satellite into space (which they can) but that ended up a diplomatic failure.
> or won't let you into the UN
Getting into the UN hardly really means much. There are many nations in the UN nobody cares about. There also are nations not in the UN yet very relevant (e.g. Taiwan which was among the UN founders).
For instance: