Biden is almost powerless while Johnson has the ability to decide England's response, with much fewer limits on that power. So it is basically guesswork to try and say how they would have done in the other country. That said, my best guess is that Biden is instinctively more cautious on Covid than Boris is, so he is stricter than Boris would have been. Also, while it does not save any lives, Biden gets bonus points for not breaking his own rules.
Johnson just announced the end of most COVID restrictions, which were stricter and included vaccine passports, two days ago. Biden has actually been taking the lighter-handed approach as more people become vaccinated and boosted. So while Biden has less direct power than Johnson does, he has been doing what he can to get the open the country back up even though it's states and localities that have the final word, for better or worse.
And yes, Johnson also has sh!t on his face for hosting a drinking party in May 2020.