Unfortunately Openwrt doesn't support the RB2011 series. Mikrotik uses YAFFS which isn't upstream and probably won't ever be. If you search the forum for RB2011 you can find the complete discussion. The last I read support was about 85% complete. The patches were asked to included but then the YAFFS issue and a NAND wearleveling issue were brought up and no work around exist. Mikrotik needs to release a boot loader that supports UBI.
The wiki is not exactly out of date. It is supported in 19.08, but not in anything newer. Support for all Mikrotik devices was dropped at the beginning of the 20.02 development cycle for the YAFFS and NAND reasons as well as lack of conversion to ATH79.
This is verry bad... What me to do is now?! This Device have quorantee, and on this device have RouterOS (Five yers license). And i dint find router on my country rev 2... no sell...