Because they're also machine type monsters, cards such as "Magnetic Mosquito" and "System Down" also hurt them (especially System Down, as it banishes Machines), and are the most common, exploitable, and obvious countermeasures to this deck since "System Down" can eliminate the presence of all Machine monsters on the field as well as those in the Graveyard (which the "Cyber Dragon" archetype are heavily reliant on as most monsters within it allow them to share it's name)
(2021-07-23) A player may only have one dungeon in the command zone at a time
The rate is terrible because you need to pay at least 5 to start the destruction, and it only gets snow lands, of course, so thats a downside
The release was far ahead of what was intended, due to Topps also releasing a Pokemon set in the early summer
If you want more protection, you can double up and run both Boots and Greaves