That will not have a very big effect. However, something like USA banning bitcoins can have huge short term effect. In the long term, crypto will still keep growing. Look at the ban by China which is a major economy in the world. Even after that bitcoin prices have grown at good rates.
You’re right because a lot of bitcoin investors reside in the USA and those who might not be in USA be worried of other countries following suit which could cause a significant drop of price but it will be soon forgotten and the price of bitcoin will go back to its usual trending.
I doubt other countries, let’s say third world ones with not much bitcoin enthusiasts in, would affect the price if they were to ban bitcoin but it would certainly upset some investors that are citizens of that country.
Bitcoin market is so resilient, we have seen it pass the test of time. When we had covid, there is a huge sell off and everyone is afraid, but we come back from lows of $3k and then have a bull run of almost $70k all time high. Same time when China bans Bitcoin mining, we did have some effect but we bounce back. So I do not think that there are more negative news that we haven't seen that will have a huge impact on the price. Even in the worst bear market in this cycle, when we see the price plummeting to $15k, and a lot of FUD, we manage to stay strong and now seeing 6 digits. So regardless it's US or El Salvador or even China negative news, Bitcoin will continue to go on and market going into it's own process to recover.