“he made up words that wasn’t needed…. So here is another example -Dayog -Fisherman. The way to say this in LK is probably Odom Sheoichaiz Dagim (Bemetzoida).”
First of all it should read “he made up words that weren’t needed”
Second of all, all languages evolve and new words are created. Did you ever wear a “tallis”? Did you know that the word “tallis” does not appear in Tanakh. According to your savara, one can’t say tallis (or tallit); one has to say beged im tzitzis al hakanfos OR something cumbersome like that.
“The same reason he made up words that wasn’t needed -like Shairootim for Bais Hakeesay. “
Shairootim means servicies, or as I would translate it in this case “facilities”. You might say to someone in English, “I need to to use the facilities.” It’s just another way to refer to the “Bais Hakeesay”