Is investing in STI ETF in the long run by DCA a good plan ?

Nope. Not a good idea. I DCA for 3-4 years (2017-2020). It didn't get me anywhere but down with a few thousand losses. When you're young, you should grow your capital.

Of course, if you are betting on the rise of STI ETF, then you could go all-in when the price is low, but whether it will go back to pre-Covid level is anybody's guess.

It's probably gonna be a slow rise however for me, I didn't stick around. It's an opportunity cost to wait.

In my opinion I think it is a great idea to consider, if you see for the past years trend for STI it usually recover back around 3.2 to 3.4k range and currently it is sitting around 2.6 to 2.9. In a long term it can be considered a relatively a decent move if you feel that it is within your investment strategy. It also provide dividend too.

I currently stopped my DCA and waiting for some correction before adding more position.

However, overall it is dependent on your own strategy and risk appetite.

Yep it is not as bad of an idea as people think, but you do need to diversify!

Personally, i will only go into es3/g3b if im old / low risk taker / have a big amount of capital. You should know the sti doesnt have a lot of growth stocks but more of dividend paying ones. Usually, when companies start paying dividends, most likely means no room for improvement. Even if there are, it will not be at a fast rate.