You're forgetting some "laws". Let me list them in order of priority:
1. Business hours must be kept in sync with the important countries next to them. This is important for communications between companies. When business hours are off by 1 hour, there is 1 hour less to communicate with your neighbour countries at business hours. That is 12.5% of the business day you cannot reliably contact another company in another country.
2. The clock must be equal to these important countries to not make mistakes when setting appointments.
3. Business people with kids have to bring their kids to school before business hours start. Schools start before business hours, about 30 minutes up to an hour earlier.
4. Shops open relative to business hours.
The reality is that north-west EU will do whatever Germany does. Germany wants GMT+2. That means that all countries west of Germany that follow Germany will have post 10 o'clock sunrises in winter, 2 hours after people get out to bring their kids to school & go to work.
Just spitballing, but I take it you don't participate in many multi-TZ meetings.
1. That's a non problem. If you're in meetings 8h/day the last of your worries would be TZ. Plus, such a time zone difference already exists today between e.g. France and the UK, Portugal and Spain, or for that matter within the US and other countries, and even within US states themselves (see AZ).
2. No it doesn't. What's most problematic when setting appointments actually is when daylight savings changes times. During the switch your regularly scheduled meetings may get messed up, times that worked for an entire remote team might no longer work for a week or two, and mishaps on new meeting schedules are all over the place. See e.g. https://youtu.be/84aWtseb2-4?t=230 to get a sense of how nutty it can get.
3. 4. I'm failing to see how using daylight savings or not makes any difference.
> The reality is that north-west EU will do whatever Germany does. Germany wants GMT+2. That means that all countries west of Germany that follow Germany will have post 10 o'clock sunrises in winter, 2 hours after people get out to bring their kids to school & go to work.
As a french I don't see the problem with that, I'd much rather have more sunlight in the evening when I can actually go out and do stuff
Maybe you don't, but it really messes with your biological rhythm to get up before dark. If you get up, go to work and start your job all while it's dark outside, it is really hard to get going and not getting depressed in the long term.
Maybe not for you, but for many it will be.
The only daylight people will experience is when they leave their job. That's rough.
When business hours are off by one hour, there is one hour less to communicate with your neighboring countries during business hours.
If you had an eight-hour work day, a one-hour time offset from a neighboring country would mean you overlap with them for seven hours, and they overlap with you for seven hours. One of you loses an hour off the beginning of your day, and the other loses an hour off the end, but that does not add up to a loss of two hours.
This is especially obvious when you have an eight hour workday with an eight hour time zone offset. That does not mean you have sixteen hours less communication time.
re: 1 and 2. Yet lots of businesses in US states communicate with other businesses (and company locations) in different time zones including those in adjacent states in some cases. To say nothing of other countries. Dealing with timezone differences is routine for many people (and fortunately something that computers mostly handle pretty well except when you forget to provide them with timezone info).
There's a good argument for not proliferating timezones beyond a certain point. But, given they exist for good reason, you're always going to have lines that people need to communicate (and even commute) over.
>1. Business hours must be kept in sync with the important countries next to them. This is important for communications between companies.
I'm going to echo another responder here: this is total BS. Here in America, it's completely routine for companies on opposite coasts to do business with each other, and there's a 3-hour time difference year-round. If we can handle that, surely Europeans can handle a 1-hour difference.
There are also union laws that mandate overtime pay off hours. These hours are often defined to be out side of 8:00-17:00, incentivizing businesses to keep open during these hours.
1. Business hours must be kept in sync with the important countries next to them. This is important for communications between companies. When business hours are off by 1 hour, there is 1 hour less to communicate with your neighbour countries at business hours. That is 12.5% of the business day you cannot reliably contact another company in another country.
2. The clock must be equal to these important countries to not make mistakes when setting appointments.
3. Business people with kids have to bring their kids to school before business hours start. Schools start before business hours, about 30 minutes up to an hour earlier.
4. Shops open relative to business hours.
The reality is that north-west EU will do whatever Germany does. Germany wants GMT+2. That means that all countries west of Germany that follow Germany will have post 10 o'clock sunrises in winter, 2 hours after people get out to bring their kids to school & go to work.