I think this is worthy for Delta to test it out.
International travel will not just open up and go back to normal. There will be restrictions. Different countries will put in different restrictions, be it health screening or quarantine requirement. "Travel Bubble" is one of them, e.g. Baltic, Aus-NZ, all-EU, etc. The other one that has been floated in some countries is that they will open to "business travelers" only. This makes sense because it will limit the number of travelers greatly but it will bring in the high rollers. So if your country or city is a premier business destination, you may get only 10% of normal incoming traffic but 40% of the travel income. Virus follows people, not money. Each additional person you allow into your country increase the chance of virus coming in proportionally, regardless of high much money that person is spending in your country. Naturally, country will want the top spenders if they are only allowing in a limited number of people. You essentially get the best of both worlds. With that context, it makes sense to fly high-end business-class only flights.
If Delta is really doing this, they may limit it to a small number of 757 and 767, where they will fly to major business destinations only such as HND, ICN, LHR, CDG, FRA and AMS from their primary US gateways and also primary business destinations such as SEA, BOS, ATL and JFK.
319/20/21 332/33 342/43/45 359/51 388 707 717 732/36/3G/38/39 74R/42/43/44/4E/48 757 762/63 772/7L/73/7W 788/89 D10 M80 135/40/45 175/90 DH1/4 CRJ/R7 L10
AY LH OU SR BA FI LX
AA DL UA NW AC CP WS FL NK PD
CI NH SQ KA CX JL BR OZ TG KE CA CZ NZ JQ RS