TLDR: I bought a moka pot. Indeed it is stronger and way more tasty than the Nespresso capsules.
A longer answer: I was using the black capsuls which are designed for espresso size cup, but ran it twice in Lungo mode, thus I assumed I'm getting a weaker coffee.
However, I started questioning the quality of these capsules after getting a free sample of cocoa capsules. The smell was spot on, but the taste quite lackluster. By an interesting coincidence, I had an actual cocoa bag at home and brew myself a proper cocoa on a stove with milk, and the final result was a night and day to the capsules.
After that, I went to a friend who has the spinning Vertuo machine, which makes coffee designed for bigger cups. Sicne I was deluding mine, I assumed the coffee from that machine will be stronger, but it was quite similar to mine.
Compared to those, the moka pot, like the cocoa, has a proper rich taste and strength. Even when I make it "on the weaker side", it still beats the capsules by miles, which tastes like coffee dust rather than proper coffee.
Now, I'm not saying capsules are bad, and I guess they are more tastey than instand coffee, but they don't come any closer to fresh grinded coffee made in a moka pot (like bottled orange juice compared to a freshly squized one).
Of course, all said here is my pure subjective opinion.