Mechasaur, Platform Builder is not a Mario game creator. In addition, Mario Builder didn't allow us to customize our own enemies, items, projectiles, blocks etc. Also, it did have any way to add some special effects via command prompt although it was powerful enough to make something really special using some tricks... Anyway, you didn't have any problems using MB although it didn't allow to make some new enemies, tileset movement and such like in SMBX. I see you have become some big kind of critic and such but in reality, you seem to have left behind a time. PB allows you to make a lot of things that MB didn't allow. Of course, you may be unable to create a Bowser who cases you just like in MB but it allows you to make every kind of situation and challenge that MB allowed to do and more. Comparing PB with SMBX is that you can't make everything that you can make with SMBX but it probably have some preferences in front of SMBX already and it is a lot of easier to understand and learn.
Shouldn't you just open PB and try to make something by yourself?