And it is. It really is.*
Tcha! you may say (if say is the right word to describe the production of the sound tcha), up to your very eyeballs in extra food items no one really fancies much, drink that's going to make people far too honest, and presents that are doomed to hang about getting dusty until at last they fulfill their rightful destiny adding to the country's landfill problem.
Luckily for the British, though, we have a get-out clause about being jolly because for us it doesn't necessarily involve happiness. Someone British can be jolly unhappy, or jolly miserable, or even jolly cross.
If someone British is jolly drunk and wants, say, to tell the whole world about the tragic end of his relationship, he can even be jollied into cheering up and singing I will survive, instead.
The British can even go on a jolly, which is a pleasure-trip paid for by someone else, usually an employer. It might even involve sailing in a jolly boat which is flying the Jolly Roger - though it's more likely to involve a bad meal, slightly slurred speeches, and a lot of wondering about whether one has the courage to make a really radical career-change.
'Tis the season to be jolly?
Oh, what the heck, it's better than being miserable, isn't it? Pass the mince pies, will you? All together, now!
Fa la la la la, la la la LAH!
*Thing To Do Today: be jolly. This word comes from the Old French jolif, and before that probably from the Old Norse jōl, which means yule, the Christmas season.