It is more convenient than using the constructor because the only limited kind of expression is allowed in a base constructor call.
Also, the object initializer syntax can be used.
Hidden properties are used when the type is the base class. It caused issues when `DrawableHitObject` logic is factored out to `PoolableDrawableWithLifetime` because it is using the base `LifetimeEntry`, not `HitObjectLifetimeEntry`.
It was added in c9f38f7bb6, which
specified 2021 in another place (and was committed in October of 2020
anyway). Update the year so that it doesn't get culled prematurely.
There were cases in the editor where rewinding of transforms would
leave the `DrawableHitObject` in a non-`IsPresent` state, resulting in
this scheduled logic never running.
This would in turn cause ghost hitobjects, which disappear under certain
circumstances.
Reproduction:
- Open editor to empty beatmap
- Place single hitcircle at current point in time
- Drag editor timeline backwards to seek before zero, and wait for
return to zero
- Select hitcircle in playfield
- Drag hitcircle to right in timeline, triggering a start time change