These are the new options (File>Configuration).
Variable Tech Year uses the rules for era-based play introduced in some of the later TROs and fleshed out in Interstellar Operations. Rather than having a fixed rules level, equipment moves from experimental in the prototype stage, to advanced when it enters full production but is not yet generally available everywhere, to standard when it is commonly available.
Use Game Year lets you select a year other than the unit's introduction year to calculate tech level. The introduction year (set on the structure tab) is used to determine whether the tech exists, and the game year is used to determine its rules level. This option is only available when the variable tech level option is in use.
Show Faction is what is demonstrated above: some factions have access to certain pieces of tech before others, or may have it at a different rules level if variable tech levels are in use.
Show Extinct Tech will show tech that is no longer in production (which is what extinct means in the tech progression rules, rather than non-existent). This can be used in situations like a campaign that finds a cache of SL equipment during the succession wars and refits some units, or building a Jihad-era retrotech unit after primitive tech has gone out of production.
Unofficial Ignores Year just presents all available equipment regardless of when it was introduced in the game's time frame, if the tech level is set to unofficial. It will still filter according to Clan/IS tech base unless mixed tech is chosen.