The disadvantages of hibernating.

You have got it completely wrong. The truth is that Hibernate and Sleep are two, entirely different functions, and also that Hibernate is very synonymous with Shut Down.

• Sleep puts your session in RAM. This is an extremely efficient power function as RAM is very snappy, and you will not experience stability problems because the system isn't completely powered off. You can think of Sleep as a pause button for Windows, it momentarily stops your PC, and when you're ready to go, just hit Play, and Windows will be right there waiting for you instantaneously. This mode is recommended if you are going to leave your PC for a few hours, or maybe even overnight. This mode draws extremely low amounts of power, only enough to sustain RAM. The average laptop 2-3 weeks or longer when in sleep mode.
• Hibernate takes your session, stores it on your HDD, and then shuts down everything*.* Everything. When your PC is turned back on, the system loads your previous session from the HDD. Some older systems can bog down over time because of Hibernate because memory, temporary files, and other Windows components need to be flushed, or refreshed, from time to time. Use this mode if you want to Shut down your PC completely, yet you have unsaved work that you don't have time to finish up. This mode does not use power at all, as it basically shuts down your PC. Therefore, it does not extend battery life.

I advise my clients to restrict hibernate/sleep functions for usage only in absolutely needed circumstances.  Hibernation frequently causes problems which are seldom ever fixed.  Myriads of causes you can spend weeks trying to find.  Just not worth it.

Background:  The concept of sleep/hibernate was designed to extend battery life.  If you are not running on a battery or never do, the very idea is quite useless.  If you are doing it because your computer takes a long time to startup, fix that problem.  Under normal circumstances if you are finished using the computer and do not plan to use it again for at least several hours, shut it down.  Leaving it running continuously is a sure way to shorten your computer's life

There are no significant disadvantages, however:

• When you enable hibernate, the hibernation data file must be present. Depending on your system, this file could take up anywhere from 2-10 GBs of space.
• On older systems, it's beneficial to shutdown because it can help flush up the 'gunk' over time.

Otherwise, there is no disadvantage/harm to hibernating.

I have never heard either of Sleep or Hibernate starting to misbehave as systems get older...  it either works or it doesn't and if it doesn't, you figure out why and fix it.  There are no "moving parts" involved to deteriorate or suffer in performance over time unless electrons start to move slower.

Back in the XP days when I had 256MB RAM (MS recommends 128MB) , I used to Hibernate all the the time since resuming was a little faster than a cold boot.

As I started adding more RAM (512, 2GB, 4GB) , resuming from Hibernate started to take longer and longer because the size of the hiberfil.sys file got larger and larger (this makes sense) so when I got to 4GB RAM, it took longer to resume from Hibernate than it took to cold boot (~18 seconds to cold boot) so I quit hibernating.

On a Windows 7 system I tested today it has 4GB RAM and resuming from Hibernate I timed with a stop watch and it took 94 seconds to resume and a cold boot only take 19 seconds so why Hibernate?  The more RAM you have, the longer it will take to resume from Hibernation.

Sleep lets you get running again faster but I never suggest Sleep for it is inherently dangerous since if you have unsaved work and files open and for some reason your system loses power, your work could be lost, files may be corrupted, etc. and that is not why Sleep was invented.

If you use a password on wake there is no difference in hibernation and using shutdown.

If using a ssd = solid state drive is about the only reason to disable hibernation in windows 7 to disable unnecessary writes.

Amount of ram has to be considered and what programs are open for a system whether it will like or not hibernation in win-7.

If not using a back up battery system hibernation is a good feature

Power outages will happen and that is where hibernation kicks in as a good thing.

But if over night.... I'd normally shut down there's no good reason to hibernate all night...

Win-10 is another story all together most older systems/ mother boards do not support fast start features win-10 uses.