MacBook Unibody from 2009 was very serviceable[1]. You only need to remove 10 screws, no glued parts, no soldered RAM or storage.

[1]: https://www.ifixit.com/Teardown/MacBook+Pro+13-Inch+Unibody+...

No, the Unibody chassis have been in use since the 2008 MacBook Pro and they have been perfectly repairable, until 2012 and later 2016 where Apple started soldering previously replaceable components to the logic board.

They did make it a royal pain in the ass to work on the keyboard or trackpad though, but anyone who works on MacBooks daily can gut one in minutes.

Current model designs, yes; but the series from roughly 2009-2015 (and the 2011/2012 models specifically [0]) are some of the most repairable and hackable models they've made: pull the bottom panel off the Unibody frame, and all the parts are laid out. Swap RAM, replace the optical drive with a 2nd hard drive, replace the battery, fans, whatever.

Whether the "sealed-airtight-with-glue" patterns of modern Unibody designs are truly necessary (or desirable) to achieve design goals of thinness and weight is hotly contested. :)

[0] https://www.ifixit.com/Device/MacBook_Pro_15%22_Unibody_Late...

No, the decision to solder components to the logic board probably comes from making it thinner, not from the unibody design.

The 2011 MBP was unibody and it was a lot more repairable but also thicker.

Having owned both a 12" G4 powerbook and a 2008 MBP (unibody), the unibody was far far easier to get inside of and replace most parts.

I think when designed considerately, unibody type construction can make disassembly significantly easier.