In 2238:
* Tycho is dead. Grilled by a flamer in Necropolis while he joined the Vault Dwellers quest. Rest in Peace.
* Ian is supposed to be dead. His cameo in FO2 has been cancelled alongside with an entire location. (The Abbey). Thank god.
* Dogmeat died in the forcefields in Mariposa.
* Not much is known about Katja, she was a useless Follower in FO1 anyway (if we just talk combat)
* Marcus is in the middle of building up a town and getting rid of problems dealing with interracial issues long before the Chosen One shows up.
* Lenny is just a small fish in the bowl, bemoaning his choice not to help the vault dweller.
* Myron is just about to (further) develop Jet. His big role in Reno is yet to develop.
* Cassidy is yet to arrive in Vault City/building his bar.
* K-9 is everything but alive.
* Goris is a talking deathclaw and disqualifies itself by that mere fact in 2238.
* Miria/Davin don't really count as companions anyway, with their usefulness pending between "none" to reaching negative numbers.
* Sulik did shit and is paying back with work for this mistake.
* Skynets inanity level exploits normal grounds and disqualifies tenfold of 2238 believability.
This all besides the fact that it would look ridicolous to have Marcus1, Marcus2, oh hai Marcus3, ah there is Pwnz0rxD13095, his follower is Cassidy2092331313, let's welcome him! Companions are ok, as long as they make sense and have enoug variety.