https://www.zabbix.com/documentation/5.0/manual/installation/requirements
https://www.zabbix.com/documentation/5.4/manual/installation/requirements

Why 5.0 says: "1.x, 2.x" which is fine, while 5.4 says: "PostgreSQL 12 with TimescaleDB 1.7/2.0", which is not so true ?

I have Postgresql 12.7 and Timescale 2.2 or 2.3 - and they work fine.
Documentation could be improved.

I'd avoid to mention exact recent versions (like 2.0 above) because it may get outdated.
Maybe it makes sense to state by a short sentence that this may not reflect currently available versions?