Samsung note 10.1 GT-N8013
Some apps won't download. Get message not compatible or app not optimized. I have cleared cache and data . Still does same thing.
Few things could be happening.
A few apps may simply be incompatible with tablets, I've experienced that over the years. A lot of developers build apps for phone and don't bother to optimize them for larger screens found on tablets.
That tab is also nearly 7 years old, Samsung hasn't provided a software update in a solid 4 or 5 years meaning it's on a dated version of Android. Many app features require newer versions of Android, so if a developer includes those features it makes the app incompatible with older Android versions. I think your tab is actually the oldest version of Android that still has access to Google services like YouTube.
I've still got that tab, I only use it as an alarm clock and to sketch on occasionally. It's too dated, slow, and incompatible for me to use regularly at this point.