It is a feature on your phone that uses part of your phone's internal storage as RAM/memory also called virtual RAM or virtual memory. It allows more apps to stay open in the background. You can select how much storage is allocated to the virtual memory in Settings>Device care>Memory>RAM Plus. You have to restart your phone for any changes you make in RAM plus settings.
If you are a heavy multitasking person, you can switch between apps without worrying about starting over again when minimised apps and locked apps are automatically closes in the background.
Does it drain battery quickly?
From my personal experience, RAM plus does not drain battery.
Does it cause wear quickly on the internal storage?
Maybe. You might think there are frequent read/write/delete which will cause wear on the internal storage and at some point the the 'storage' will become slow. Are you worrying about it? If yes, then uninstall WhatsApp from your phone.
If everyday or mostly everyday some contacts post one or more status, once you are connected to Internet or you view the status in the status tab, the status is downloaded (write) and saved (write) to the internal storage in the following directory: Android>Media>com.whatsapp>WhatsApp>Media>.Statuses. As a WhatsApp user, you already know that after every 24 hours the status is disappeared, that mean the status files gets deleted (delete). This cycle repeat every time someone post status. So, this is definitely causing wear to the internal storage!
If no, enable it without worrying. I have it enabled from the day I got my phone.
Does it hurt performance?
I think yes, personally. Sometimes there are little lags here and there but not noticeable that much. After a restart it's smooth like butter. You know what, if you restart your phone every week (I prefer Sunday’s) you should be fine. Or once you are done with multitasking on your phone, you find your phone lagging, clear recent and turn on power saving with all power saving options enabled, wait at least 15 seconds, lock your phone, wait 1 minute, unlock your phone and turn off power saving. The optimal performance of your phone should be restored.
RAM Plus is a feature on Samsung Galaxy phones that uses storage as virtual memory to expand memory. This feature can be used to launch apps faster and have more apps open in the background. but bear in mind that it can cause high consumption of your battery life since there would have a lot of apps that are running in the background
