This guy can easily destroy the entire mondstadt if he wants to.
Varka militaristic power as the head of favonius knight, seamus morality power as the head of favonius cathedral, venti and istaroth godly archon aetherial power were all btfo'd hard by this one single guy as the owner of mondstadt biggest wine production house.
If diluc decided to mess around a little bit with his product, by limiting his dandelion wine or even apple cider production, maybe by taking a little bit more profit from it, then the entire mondstadt economy will be weakened in a span of a few days, not even a week; If he decided to toy around with his authority, by replacing his mondstadt maids and workers with sumeru foreign workers, then this entire mondstadt as a nation is finished; the entire economy and mora circulation are so fucking done. If you make people poor, no amount of muscle, moral, or divine miracle that will convince them to stay, not even if venti revealed himself as barbatos in front of his now hopeless and nihilistic people that are already packing their bags or on their way to other nation for a better life; knights and military will all leave their service, eula and mika will give up their badge alongside amber, the entire cathedral will be emptied, rosaria will leave her post, leaving barbara as the only working sister there, stores will all be closed, so does the bar and taverns, diona might be cheering over this alcoholic exodus, but another wave of sadness will reap on her soul as she witnessed her alcoholic father hanged himself after months experiencing addiction episode and beat his daughter ass up with his belt because now its impossible to drink alcohol in mondstadt due to diluc extreme monopoly business over wine and cider production, and venti as the one and only archon in there will be weakened overtime because people wont pray to him anymore. People of mondstadt will probably go to liyue as the nearest neighboring nation or somewhere else to live a better life. Mondstadt is going to be empty, absent of life, though higher ups like jean, varka, hexen, and maybe dahlia will probably stayed, witnessing the sinking of their beloved land for one last time, cant say the same for the rest though. The other archons wont claim the land since they are still respecting venti sovereignity over his region, but some chuds like treasure hoarder, vile fontainian businessmen, or fatui are going to inhabit old mondstadt on their whim and do their business in there, maybe even building their own base in there. Diluc, with his mora that he piled from years of monopolizing wine import and production business, can pay everyone to be his personal guard, to work on his field, hell he might even working with other faction in order to expand his capitalistic tyranny in the new mondstadt and securing his safety at the same time. Dandelion wine is going to be produced still, but it wont soil the fertile land that once gave birth to it. Venti will probably weep on his now rotten and half destroyed statue as evil diluc laughed while counting his mora in front of his fireplace, unable to beat him with his power since nobody prayed or believed in him anymore. Tsaritsa will saw the entire situation, being sympathetic to her old friend, and say to herself "freedom always come with a price"