Europe is opening up to US citizens. [Forbes] So why are they not opening up their border for Europeans [and UK]?

From Forbes, Europe is opening up to US citizens. So where is the return love? " From Italy, Greece and Portugal in southern Europe to Germany, Norway, Denmark and Latvia in Northern Europe, the continent is reopen for travel and U.S. tourists who want to visit the region are being welcomed for leisure and other non-essential travel purposes." Forbes - https://www.forbes.com/sites/ceciliarodriguez/2021/06/27/europe-opens-to-americans-with-and-without-covid-passport-pack-your-bags-as-amsterdam-lisbon-paris-await-you/?sh=6fd54803fa29