Does the news of Tesla investing $1.5 billion in Bitcoin and expects to start accepting the cryptocurrency as payment increase your confidence of the future of cryptocurrency?

Yes because

1) Major institution starting to keep Bitcoin as hedging against lost since US government kept printing USD and the USD value will only kept decreasing.

2) There's a limited supply of Bitcoin for mining. Once these runs out, whatever available will be just all those flowing in the market. For the lack of Supply and increasing demand due to #1 and much suitable than gold as hedging.

It will rise to all time high in time ! Just have to buy and ignore the rollercoaster.

Other than Elon Musk (Tesla), there's also interest & dedication by payment firms - looking into bitcoin & other crypto use cases (eg Paypal). These are positive indications that does add confidence boost to start investing in cryptos.