I thought the word had spread that the NSA is pretty good too. Yes, chinese network gear is often seen by some as compromised by design. Though recent news reports suggest that gear from US-companies might get manipulated after it leaves the factory (see here or here). Other manufactures are not above suspicion, too. Pick your poison!
Picking old hardware is not a solution to this problem:
Old stuff is more likely to break and gives your admin headache.
Often the support is discontinued. Therefore no security updates (or new backdoors as you like ;-) ) => There may be known remote exploits but no one feels responsible to fix it.
The security features are out-dated. For example: if you use an old access point and encrypt your wireless network using WEP any script kid breaks your encryption in 5 minutes or less.
Old network gear is slow. In particular if you use encryption that slows everything down.
It is unclear / unproven if or at which point some state may have started to plant backdoors. 3 years ago? 5, 7 or 10? (You seem to be especially afraid of chinese manufacturers: they deliver components and did so for years.)