Rising fares are not just isolated to QR, and capacity overall is still lower than pre-COVID levels and flights are fuller than ever. Check out the IATA reports on this, recent US CPI data, the Air Monitor 2023 report from AMEX as well as recent statements from LH's and DL's CEOs amongst others.

Ticket prices are dynamic, an airline won't look to pursue being competitive for every single connection or route but would look at the total revenue potential. If the routes you are looking at, at specific dates QR might be way more expensive than the competition it doesn't mean that it applies across the network at all dates. For example ex-JFK QR is selling business class tickets to CMB for almost 1000 euros cheaper than ex-FRA for those dates.

If you look at your dates it seems QR is scheduling the 24J 77W and 24J A35K and the 22J 787-8 to FRA, that is only 70 seats over 3 flights compared to 84 seats over 2 flights when they had 2 daily 77W 42J at some point in the past. They have less business class seats to sell for now so they can better manage their yields, if they later swap to a higher J configuration that might mean they could make more lower fares available.

If you want to go on QR to CMB from Germany check out departing from BER where the fare is around 3200 euros and QR is the cheapest 1 stop option from BER over most days September and October. Departing CPH and MXP is similarly priced.