There is unfortunately still some oil import despite sanctions:
https://www.euractiv.com/section/politics/news/russia-continues-to-ship-oil-directly-to-the-eu-despite-sanctions-investigation-finds/
it looks like a trade war with the US is coming and having the option to reduce US oil would be very usefull.
Yes, 100%. EU cannot rely on USA anymore, for at least next 4 years.