What are the tradeoffs of a cantilever printer design?
Cantilever printers constrain the X-axis carriage only on one side and have a free hanging side. This means, that the X-beam has to be rather sturdy and is limited in length, making them usually quite small machines. 

Another tradeoff stemming from this source is, that they have to stiffen this one connection as much as possible. Any play on the connection leads to increasingly large errors the further the printhead is out from the Z-Axis and can lead to bad prints, banding and total failures of prints. This behavior, at least on the TronXY-X1, is sometimes called Z-Wobble and has brought up some aftermarket modifications. For example, this bracket constrains the movement of the X-cantilever.

While all axis would be affected by bad constraints, a cantilever suffers the most: The cantilever (if not well constrained) can deflect in both XY and XZ plane, pretty much opening a cone with the tip at the leadscrew nut. A one side-leadscrew portal design can only deflect in the XZ plane, opening an angle along with the center in the leadscrew nut. A double leadscrew design has, constrains both ends of the X-axis and prevents deflection but could suffer from bending the portal bar.

The main benefit of a cantilever design is that being of a rather simple design with few moving parts, understanding as well as repairing and modifying the motion control system is fairly easy. The ease of access and low component number also allows reducing manufacturing costs to some degree.

Another thing of note is, that these printers usually have a fairly small form factor, allowing them to be used in small workshops without taking up too much space. However, their build-volume to occupied-volume ratio usually is not as good as other designs - printers with a much larger build volume just get a much better ratio there.