Have you tried to use the NOCOMPRESS option explicitly?
What is the result of select * from dba_ilmpolicies;?
What is the result of select banner_full from v$version;?
What is the result of select value from v$parameter where name = '_exadata_feature_on';?
If you running this on a EE-ES, DBCS EE-EP or ExaCS system, then I suggest to contact Oracle support.

SQL> r
1 CREATE TABLE t4 (
2 key INTEGER NOT NULL,
3 value VARCHAR2(30 CHAR) NOT NULL,
4 CONSTRAINT t4_pk PRIMARY KEY (key)
5 )
6 SEGMENT CREATION IMMEDIATE
7 MEMOPTIMIZE FOR READ
8* tablespace USERS
CREATE TABLE t4 (
*
ERROR at line 1:
ORA-62141: MEMOPTIMIZE FOR READ feature cannot be used with COMPRESS option

But USERS tablespace are not with COMPRESS clause, nor I’m using COMPRESS clause on create table.

SQL> @printtbl8 "select * from dba_tablespaces where tablespace_name=''USERS''"
TABLESPACE_NAME : USERS
BLOCK_SIZE : 8192
INITIAL_EXTENT : 65536
NEXT_EXTENT :
MIN_EXTENTS : 1
MAX_EXTENTS : 2147483645
MAX_SIZE : 2147483645
PCT_INCREASE :
MIN_EXTLEN : 65536
STATUS : ONLINE
CONTENTS : PERMANENT
LOGGING : LOGGING
FORCE_LOGGING : NO
EXTENT_MANAGEMENT : LOCAL
ALLOCATION_TYPE : SYSTEM
PLUGGED_IN : NO
SEGMENT_SPACE_MANAGEMENT : AUTO
DEF_TAB_COMPRESSION : DISABLED
RETENTION : NOT APPLY
BIGFILE : NO
PREDICATE_EVALUATION : HOST
ENCRYPTED : NO
COMPRESS_FOR :
DEF_INMEMORY : DISABLED
DEF_INMEMORY_PRIORITY :
DEF_INMEMORY_DISTRIBUTE :
DEF_INMEMORY_COMPRESSION :
DEF_INMEMORY_DUPLICATE :
SHARED : SHARED
DEF_INDEX_COMPRESSION : DISABLED
INDEX_COMPRESS_FOR :
DEF_CELLMEMORY :
DEF_INMEMORY_SERVICE :
DEF_INMEMORY_SERVICE_NAME :
LOST_WRITE_PROTECT : OFF
CHUNK_TABLESPACE : N