The Two Georges. Why does a union of North American and Britain have to be portrayed as technologically way behind the current day? And why are there always zeppelins instead of planes? And cars use steam engines instead of regular gas. What if an alternate reality was technologically up to date in a parallel universe?
I don’t think it is actually technologically way behind the current day. Here's what it says about planes:
Bushell savored his feeling of contentment with the world; he knew it too seldom. He leaned back in his chair, peered out the window once more. Suddenly he pointed. “Look! There’s an aeroplane!”
“Where?” The fat man stared. “Ah, I see it. Not a sight one comes across every day.”
“Not in peacetime, certainly,” Bushell said. The aeroplane flashed by at breathtaking speed, twin wings above and below its lean, sharklike fuselage providing lift. It was gone before Bushell got more than a glimpse of the blue, white, and red roundel on its flank that announced it belonged to the Royal North American Flying Corps.
The fat man puffed moodily on his cigar. “So much speed is vulgar, don’t you think?”
Useful for the military,” Bushell answered. “In civilian life, though, there’s not usually much point to dashing across the continent in ten or twelve hours. You hardly have the time to accomplish anything while you’re traveling.”
“Quite, quite.” The fat man’s jowls wobbled when he nodded. “If you need to get anyplace in such a tearing hurry, chances are you’ve either started too late or, more likely, put less thought into your journey than you should have.”
And here's what it says about TVs:
A patch of light in a dark doorway made Bushell’s head whip around as the steamer passed through an urban stretch. When he saw the doorway belonged to a tavern, he relaxed. “I was afraid that might have been a fire,” he said, “but it’s just a televisor screen.”
“Nothing like getting together with your chums after a hard day, soaking up a pint or two while you watch the cricket matches or rugby or tennis or whatever happens to be showing,” Samuel Stanley said.
“Keep your eyes on the screen and you don’t have to think about what ails you - or much of anything else, come to that.
They passed a trafficator whose wigwag signs gave cars on the cross street the right of way. “Do you know,” Bushell remarked, “one of the airship passengers was boasting at supper last night that he had a televisor screen in his own home.”
His friend turned to stare at him, incredulous distaste on his face. “You are joking, I hope.”
Bushell raised his right hand, as if he were about to stand in the witness box. “Upon my solemn oath.”
The wigwag switched. He put the steamer back into gear.
“Why would anyone want such a thing?” Stanley said, not so much to Bushell as to the world at large.
“Wireless is one thing: you can read or talk or do anything else you care to while it’s on. But a televisor screen ... if it’s showing something, you bloody well have towatch it. Suppose you have guests? I’ve never heard of anything so, so vulgar in all my life, I don’t think. Besides, televisors don’t come cheap. What did this chap do, anyhow?
So, it sounds like the Two Georges is close technologically to OTL, but for some reason, social pressures in the Two Georges mean that planes are exclusively in military use, and TVs are exclusively in bars and other public places.