Those hypotheticals sure would suck, if they ever happen. Until then you can easily avoid worrying about 2 and 3, and for 1, simply leave the PC's remote out, and put the TV's remote somewhere inaccessible.
Also for extra confidence on 1, you can often disable the TV's wireless/bluetooth scanning (so other devices can't access it), at the "cost" of the TV's own remote no longer working. At least my Samsung (QN90B) offers that.
Also for extra confidence on 1, you can often disable the TV's wireless/bluetooth scanning (so other devices can't access it), at the "cost" of the TV's own remote no longer working. At least my Samsung (QN90B) offers that.