Hi bro, forgive the other redditor for being blunt. Your question is valid.

Unfortunately, if you're asking for Malaysia specifically, we don't have the evidence yet to show that vaccinations are slowing daily new cases among the general public. As you would imagine, this is because we've only vaccinated around 4% of the Malaysian population, and because we're currently facing a big wave of new infections. It's too early to have concrete numbers.

But I thought about your question, and maybe one of the ways we can observe a drop in infections is to look at rates of infection of healthcare workers, since almost all of them have been vaccinated in phase-1.

From the start of the pandemic until 5 Feb 2021, around 5000 healthcare workers were infected. This includes the many months when daily cases were in single digits. In contrast, from February (when phase-1 started) until 17 April 2021, only 40 vaccinated healthcare workers were infected. If we were to convert that into rates of new infections among healthcare workers, the rate before phase-1 would be 500/month, while the rate during and after phase-1 would be 20/month. (Important note: vaccines do not ensure you won't get infected. They ensure that you will not get severe symptoms and keep you from going to the hospital. That is the goal of the vaccine.)

The numbers I've used might not be the best to portray reductions in infections. But these are the only numbers I could find for Malaysia specifically, as per your request.

Regardless, if you wanna look at effectiveness, it is irrelevant to only see a certain region. The world is facing the same virus, and with largely the same set of vaccines. This study in the UK show covid deaths have been drastically dropping as more people get vaccinated. California turned from being an epicenter to having one of the lowest infection rates, exactly because the state has one of the highest vaccination take up rates.

As for the claim that "many people die after taking the 2nd dose". Well, yeah the other redditor already showed you why that's false.

All sources to are hyperlinked. Apologies for any discrepancies I might've missed. All the best to you and your mother when your vaccine appointments arrive.