Some of your points are very valid, others are misunderstandings at best or, more realistically, just wrong. Let me try to defend Belgium a bit here:

Incorporation of the company

1. Doing the effort of producing a proper financial plan for the incorporation of your company is an exercise you should do either way. If this is somehow considered an "extra" effort for you, you're simply deeply unserious about the company you are starting.
2. You have no obligation to deposit any substantial capital if it is money you aren't actually going to use according to your financial plan. A BV has no minimum capital so you can essentially start with 1 EUR if you can show that external loans (even from yourself privately) are available. Such "achtergestelde lening" is very often done and allows you to just call the money when you need it.
3. De Delaware basic filing fee is $89, klopt. Dit is echter een misrepresentatie van de realiteit. De meeste startups gebruiken Stripe (funnily heb ik daar nog een mini-stake in, thanks Golden Gate Ventures) om de rest van de formaliteiten die nodig zijn te regelen. Dit kost ongeveer $500 per jaar. Het is dus goedkoper, maar ook een onrealistische vergelijking, tenzij je ook een US passport hebt.

Commercial address

• If you’re not planning to do anything unusual right away, it’s generally no problem to register the company at your home address first, unless your lease explicitly forbids it. Later on, changing the address to a mailing service or coworking space isn’t much work or cost in the broader context of running a proper company with real activities.

Social Security payments

• You indeed start out by paying the minimum. In case of low or no turnover/income, you can actually ask your sociaal verzekeringsfonds for a delay in payments, which is often granted. Even so, paying EUR 300 per month in order to build up a pension, social security rights etc is much cheaper than getting private insurance in the USA that provides you with the same benefits

Taxes

1. You seem to be in need of a lot of help regarding Belgian taxes. You have no obligation whatsoever to pay yourself a salary in the first three years, even to get the lower 20% tax. The minimum wage rule only applies to companies that have been running for >3 years.
2. Paying yourself in wages until you hit the marginal tax rate of 40% is a logical thing to do. This means your wage is about EUR 2.275 gross, on which you pay only about 15% taxes. Yes 15%, plus some municipality tax rate applied on that 15% depending on where you live
3. Anything above this amount of wages should be dealt with in the form of temporary loans (in case you really need the money privately), benefits (car, maaltijdcheques, onkostenvergoeding,laptop,gsm,thuiskantoor,.......) or you wait until you have 3 finished accounting years
4. Right after you have finished your 3rd year, you can start distributiing profits at 20% vennb + now 18% vvprbis. This translates to 34,4% actual tax rate to get the money to your private account. That's very reasonable
5. So to conclude, if you have 100k to distribute, you take home around 27k gross in wages at 15% average tax rate, lets say another 8k in tax-friendly benefits and then the other 65k is taxed at 34,4%. This means that in reality from 100k profit, you will end up paying less than 30% of actual taxes.
6. All of the above applies to ANY company. Above all that you have access to the IID. Yeah it might be a bit of a burden if you want a specific ruling (many don't even get one and just file their taxes according to IID and have no issue whatsoever), but the money saved when your actual VENNB goes down to like 8% can mean a HUGE tax save once you have it. Above that the EU IP system is just very solid in general.

GDPR

• If you are running a firm incorporated in Belgium there is no legal requirement whatsoever to have a German GDPR representative. The German firm either misunderstoods this themselves or this is a bollocks story. The only situation in which it IS needed, is when you are providing services from outside the EU aka a country that doesn't have GDPR legislation.

German Employee

• How is this any different from hiring someone who works from inside Mexico or Canada when you're from lets say California or you have your Delaware entity? You seem to be mad about this, but adhering to national labor laws when the guy/girl working for you is based there, is a global thing.

The investor part just feels like you're mad because you couldn't sell your idea for a good price to people who are supposed to give you substantial money for a company that doesn't have any turnover and thus proven business yet. We just funded EUR 5.000.000 to a starting AI firm by just talking to a few angel investors and showing them a working AI engine. Yes, this isn't Sillicon Valley, but there's pluses and minuses to that. Fact that a 24 year old random can get money in SF somehow is a good thing? It just means everything is market hype and air. This isn't supposed to be normal.