Two books wouldn't even last me for a weekend city break, let alone a week/fortnight's holiday.
I always take my Kindle when I travel. It's much lighter than physical books, I can read it with one hand, it's lit so I can read in the dark in a hotel room while DP is asleep at night and in the car if we're driving at night, and it means I have access to thousands and thousands of books so I can choose exactly the kind of thing I'm in the mood to read at that particular time.
Prior to owning a Kindle I used to pack so many books that it would send my luggage allowance over the weight limit, and even then I would inevitably think 'Hmm, I've got eight to choose from but none of them are the type of think I actually fancy now...' and would end up buying more at the airport and/or seeking out a bookshop wherever we were staying.
To be fair I still seek out a bookshop wherever we're staying, but out of interest rather than desperate necessity.
OP, I see kids reading all the time, and my local Waterstones (which is absolutely massive) always has kids getting really excited about books. Younger kids with their parents, and groups of teens with their friends.
Also, although people like to moan about phones and tablets, lots and lots of teenagers in particular are more enthused about reading when they can get recommendations, talk about their favourites, post their own fanfics etc with other people - BookTok and book reviewers' YouTube channels have done wonders for getting teenagers excited about reading.