Cycling around Europe after December 2020

CreditCardChris

A friend of mine is going cycling around Europe next month but I'm a bit concerned about the border crossing process after December 31st. He seems to think not much will change and because he's a visitor / tourist staying for less than 90 days in each country, he can just show up at the border with his passport and cross. You only need a visa or travel permit if you're staying for longer than 90 days, or studying / working etc. Is this true? 
How difficult would it be for a UK citizen to travel through European countries in such a manner after December?

Thanks.

martindow

Who knows how simple or complicated it might be?   I don't think anyone is sure least of all our government.  Maybe it will become clearer as the time approaches.

He also needs to be sure his travel insurance is adequate.  A lot of insurance only cover trips of a few weeks rather than the months he will be away.  This needs a backpackers type policy.