TEXT/JSONB are stored inline IIRC unless they hit a certain size limit at which point they'll be put into TOAST - so you'll see data in clickhouse but some big values might be missing.
ClickHouse has no limit on sting data length.
MaterializedPostgreSQL engine is just very recent feature with not large adoption rate. I believe if community will use it frequently it will become more bulletproof and more edge cases will be supported. TOAST in replication protocol is just not trivial to implement.