The current Squad rush meta has drawn both praise and ire. While it does add depth to the game others believe it makes the game less accessible for new players. Personally speaking, the rush meta is great for competitive Squad and some minor tweaking would address the concerns over accessibility.
Some ideas the community has that change how rush is handled at a gameplay level:
1) The game mode Conquest Hardened
Demonstrated on Zagros during the 9.4 prelaunch livestream. Allows teams 10 minutes to FOB up before an artificial barrier drops and they can leave your initial flag caps/main bases. Notably, this allows server admins to add these layers into their rotation if they wish to not have rushing while others can simply omit.
2) FOBs cannot be placed past the middle of the map until a few minutes have passed
This allows rushes to take place off of rallies and increases risk of taking a logistics truck forward as you will have some small amount of time to survive off of a rally before you can begin building a HAB.
3) The first flags should be capped
This is more of a thought process than a specific solution that would have to differ from layer to layer due to specific scenarios.
4) Raw map design
Give early flag caps key terrain for a friendly force. A good example of this would be looking at Fool’s Road AAS v3 and adding a small hill or line of rocks that forces the road into an extra turn on the south side leading up to OP Fortress. This would reduce the high speed momentum US vehicles currently enjoy coming from the south that is critical to quickly make it up the hill and prevent a Russian cap. The north side of the hill could also have a more ideal approach or steep road added, dropping some seconds off of the Russian team’s time to get on the cap while not allowing them to have complete assurance they can own the point before US arrival.
This method not only allows combat instead of default map status to destroy rushes but also can make it more difficult for teams to become capped to main if you give them the advantage in defensible terrain. Example again: OP Fortress on Fool’s Road AAS v3. The place is a monster for the Russian team to attack with open firing lanes from North all the way to SE. This leaves a very slim NW edge and an unrealistic southern approach for a beleaguered Russian team to counterattack a camped out US Army. If you turned the OP Fortress hill 180 degrees the Russians would have key terrain to defend against the US team. On other maps such as Kokan, map designers could leave the Nexus rush open to give the INS team more options to use their mobility as a strength and keep the dream of asymmetric balance alive.
With all of the above in mind I suggest that raw map design and game modes are the best ways to deal with early rushing. It addresses both sides of the equation while encouraging the game itself to be the rule rather than arbitrary server regulations. This idea still punishes those unwilling to commit forces to obvious vulnerable areas and offers those who decry rushing their very own piece of the Squad puzzle.