I always switch my laptop off rather than closing the lid. Mrs P is the opposite. She is often found cursing her laptop. I simply press the on/off button and mine fires up every time.
Booting modern laptops is a lot quicker than it used to be, but it
still takes a lot longer than coming out of sleep. Hang on, I'll time mine...
Sleep -> ready: less than 2 seconds to get back here.
Off -> ready (including typing password, relaunching apps): 42 seconds to get back here
Once or twice a day, those extra 40 seconds would be trivial, but I have my laptop next to me and am constantly starting it up to Google things etc. 30 (say) x 40 seconds = 20 minutes, which would be an annoying amount of time typing in '
ColinJ = Lord of the Laptop 2567*&)^^^'*** and staring at a boot screen! I often want the information in a hurry, for example if someone on the phone has just asked me a question. 40+ seconds unnecessary delay each time would be a pain.
It's like dial-up vs broadband. We used to put up with webpages that took 30-60 seconds to load but now we expect them to load in 1 second or less.
*** Not my real password!
Overall I feel lid closing does the machine no good at all.
Apart from wearing out the hinges, it should not cause any problems EXCEPT if the laptop has a HDD (mechanical storage device) as opposed to a modern SSD (non-mechanical). My niece used to slam the lid down on her laptop and immediately chuck it to one side while Windows was saving its state to the HDD. I warned her that HDDs can be vulnerable to shock while in use but she ignored me. A week later she destroyed the HDD by doing just that. My laptop is SSD-only so I can close the lid and dump the device on the sofa next to me without any risk to it.