The wiki page is not outdated, we try to keep our wiki pages updated, the provided wiki link is fairly new, only 1 month old. You can always check how old is the wiki page by clicking on “View history”.
As shown in the wiki link, only CRS3xx is capable of bridge VLAN filtering in conjunction with hardware offloading. Other devices (including RB3011) requires to configure VLAN switching in /interface ethernet switch.
If you are not interested in hardware offloading, then you can use bridge VLAN filtering. Note that as soon as you set “vlan-filtering=yes”, then hardware offloading will be disabled automatically on non-CRS3xx devices.
If you have followed the guide and are not able to access the MGMT interface, then it is very likely that you did not set “switch1-cpu” (or “switch2-cpu”) vlan-mode to secure.