Set "Recently used" for "Sort order" in Task Switcher options and then:
- open 3 windows (A, B, C) one after another
- minimize window C and windows B will become active
- press ALT-TAB and window A will become active

The desired behavior is to activate window C that was minimized. It is how Windows, MacOS and even Gnome will behave in that situation.

I understand that it could be done intentionally, but then could you please implement a checkbox in Task Switcher options to make it optional.

I am not alone asking for that feature. Here are some discussion threads:
https://forum.kde.org/viewtopic.php?t=101211
https://forum.kde.org/viewtopic.php?t=99625

Currently I have to apply the below patch and recompile KWIN every time I install KDE.
kwin/focuschain.cpp
@@ -235,17 +235,7 @@ Client *FocusChain::nextForDesktop(Client *reference, uint desktop) const
 void FocusChain::makeFirstInChain(Client *client, QList< Client * >& chain)
 {
     chain.removeAll(client);
-    if (client->isMinimized()) { // add it before the first minimized ...
-        for (int i = chain.count()-1; i >= 0; --i) {
-            if (chain.at(i)->isMinimized()) {
-                chain.insert(i+1, client);
-                return;
-            }
-        }
-        chain.prepend(client); // ... or at end of chain
-    } else {
-        chain.append(client);
-    }
+    chain.append(client);
 }