Yes that's so true.. it will take years before we can see pure voice over LTE in Malaysia. Dont think anyone who are not from telco industry would be aware of circuit switch and packet switch..
Lets be clear on the definition of voice over LTE:
1.
Voice over LTE with 2G or 3G fallback, or commonly called CSFB (circuit switch fallback)
This is what being implemented in 99% of LTE network worldwide and supported by almost all LTE smartphones. Example of this is you're doing data on LTE and when you make/receive voice calls, you'll be pushed to 3G or 2G just for voice calls, and your data session will also go to 3G / 2G, hence speed is reduced. And once you have ended your voice call, your phone will go back to LTE, back to LTE speed. This is because your LTE can't handle voice calls. If you're talking about this solution, Maxis and Celcom will have it soon. I'm sure their LTE network is capable of this today.
2.
Pure voice over LTE, or commonly called HD (LTE) voice:
The difference is you dont have to go to 2G / 3G when making or receiving voice calls. Your LTE can handle it. So your data session will remain. This will require (1) nationwide coverage of LTE (I think this will only happen in 5-10years, even 3G coverage of Celcom and Maxis is now only ~80%); and (2) availability of devices that support voice over LTE (currently there is very very limited). As of today, only Korea has done this, this is because they have >90% population coverage of LTE network and they worked with their exclusive device partner to have devices that support this.