Not sure what you really meant in the title, but making it a legal tender does not mean that government are afraid of Bitcoin. Every single government entity out there would have just banned crypto straight away if they were indeed scared of it.
Adopting it as a legal tender is just a means of them to at least get something out of the people that are using it. Imposing strict KYC laws to many crypto apps like the ones I have been using here in my country so that they would trace me anytime is one example.
I know my example was not about "adopting it as legal tender", but you get the idea.
Some countries still checking with how capacity and advantage getting before make bitcoin as legal tender, I don't think with any scared problem face by several countries want to make bitcoin as legal currency payment transaction. Need to see with positive and negative side when Bitcoin have adopted as legal tender for the future. Some countries still scared with Bitcoin price fluactive and unpredictable when going down drastically give impact with their citizen losing investment assets in Bitcoin.
All cryptocurrency exchange nowadays should applied with KYC procedure and many countries have make this decision needed for all domestic exchange market, maybe this way how keep away with money laundering.