Well, yes, Europe is after all a collection of 44 countries, with 27 of them being in the EU, and three EFTA countries. So you're dealing with that many different sets of laws.
Some countries are extremely strict, others are more lax. Where I live (Norway), starting a business is pretty easy and straightforward. Other countries, like Germany, are notoriously difficult from what I've read.
And again, some countries have very strict laws and guidelines you need to follow, once you've started a certain type of business. Where I live it is relatively easy to start a LLC, but you'll need to put some money into it, and you can easily get fined - or even face jail - if you don't follow the laws for accounting/auditing. It becomes problematic, quite fast, if there's no unified codes for these things, if everyone's going to be able to operate cross borders.
Not to mention all the other laws (consumer laws, etc.)
How is Europe, much less the EU, supposed to do that?
Registering a business in Estonia is famously relatively straightforward, while it is an absolute pain here in Germany. But business registration is the responsibility of the countries themselves and it should remain that way
In Sweden and Netherlands it is quite easy and straightforward to register a business, speaking from personal experience. Tax filing is quite straightforward as well, especially for personal income tax.
Starting a company in Sweden requires (uploaded PDF from Bolagsverket to ChatGPT who summarized):
1. Prepare the foundation deed and the articles of association.
2. Identify the beneficial owner(s).
3. Pay the share capital and obtain the bank certificate or auditor’s statement.
4. Submit the registration application for the limited company to the Swedish Companies Registration Office (Bolagsverket) and wait for approval.
5. If applicable: submit a certified copy of your passport (non-Swedish citizens).
6. Apply for F-tax approval and VAT registration and wait for the decision.
7. Register as an employer if you will pay salaries.
8. Keep continuous bookkeeping and prepare the annual accounts each financial year.
9. Submit the annual report to Bolagsverket every year.
Optional:
1. Obtain business and personal insurance.
2. Register trademarks or protect other intellectual property.
3. Choose an auditor if you want one or when the company later reaches the required thresholds.
4. Register a cash register if you accept cash or card payments.
5. Meet requirements for import/export and obtain an EORI number.
6. Follow rules for buying/selling goods or services within or outside the EU.
7. Keep a staff ledger if required for your industry.
8. Follow reverse-charge VAT rules if you operate in construction.
9. Apply for permits if your specific business activity requires them.
This is not what I'd call a straightforward process, personally. Also speaking from personal experience. Sorry for the formatting.
I guess it depends what we mean with straightforward. If we mean something along the lines of "no ambiguity" then yes. If we mean something along the lines of "simple, easy to do" then no. Almost anything can be accomplished with a sufficiently long checklist. I just feel like the entire process could be streamlined and simplified.
There are dozens of stories how registering a business alone can take several months and tons of paperwork.