It all depends on your children's personalities, your family make up, the type of holiday you are on, your expectations for the holiday, your partner and if the holiday accommodation fits your needs.
It sounds like you have been very lucky, you were able to put your child to bed at a reasonable time and had a balcony and "adult time". Not all 18 months olds go to bed so easily. Some will fight for hours in unusual places, some will wake multiple times in the night, some will want to co-sleep whilst away. Some people find themselves sat in the dark in silence from 8pm every night because their DC don't sleep.
It sounds like you are blessed with an easy child. Some children have lovely calm personalities and are great company at 18m. They go with the flow, cope wonderfully with the change in routine and the heat. Some become absolutely feral turd goblins from 12m +, which when mixed with poor sleep and heat makes them incredibly hard work. Some children need their routine, their sleep and find the whole change of location overwhelming.
1 child on holiday with 2 parents who take fair turns and parent together, is wildly different to 2+ children. Also at 18m your child will go to bed somewhat early or nap in the day giving you a break. It is a whole different ball game with multiple children age 4 up who don't nap, don't want to go to bed early due to FOMO or overstimulation with entertainment. Are staying up every night until 10pm or 11pm and up at 6am raring to go. Bicker with each other and share a room so there is no away space, constantly ask for their tablets/ phones which don't work because the hotel Wi-Fi is only in the lobby so they constantly natter to go to the lobby. Complain they are "bored", pick over and at the food and only want pizza and chicken nuggets, but they are not the same as home ones. Mix that in with a partner who does f-all, takes themselves off, decides to sit on a sun lounger or in the bar or generally doesn't parent even when present and it becomes very stressful.
Then there is the expectation, some parents go abroad expecting it to be like their child free holidays. Then realise that holidaying with children means been at breakfast early, pool early and constantly playing, beach, finding things to do, finding something children will eat, going to the kids entertainment, dealing with tantrums/ bickering/ bored kids. There is little time to sit on a sun lounger with a book for hours sipping cocktails. You can't drink too much because a hangover with 2 kids who are on the go from the crack of dawn and overstimulated is a new circle of hell. Also despite having a kids club, the kids have decided they don't want to go or it's a bit shit and so now you have the kids full time when you were expecting a few hours child free.
If you are self catering, it can be very much parenting and been at home in another location without all the things that make life at home easy.
Basically, you are blessed with an easy going child, probably a partner who pulled their weight and the set up worked for you. Many of us are not so lucky.