I read a lot of books - a bit less at the moment as I commute less - but still probably more than most people. However there are so many books I would like to read I can’t read them all. I still prefer to read the full book but sometimes book summaries are useful - either to get the key concepts or as a reminder of what I have previously read.
However there are also some free sites where people have summarised books.
I have been reading the summaries by Derek Sivers for years. As well as providing a summary he also gives the books a score - I don’t always agree with them but they provide a good initial guide. I also like you can sort them by “newest” so you can see what has been added since your last visit.
I recently came across The Rabbit Hole. This has a huge number of summaries for a single person. Each summary is organised into an overall summary, key takeaways and a “What I got out of it section”.