Killing off adtech didn't reduce the number of ads seen by people in Europe or make any observable difference to anyone's lives, but did help ensure a company capable of developing LLMs could not arise,
When the internet was researched and developed, it wasn't funded by adtech, and yet it managed to develop it just fine.
---
Also, the point of GDPR wasn't to reduce the number of ads. It was to prevent massive, indiscriminate information gathering. Now, whether that was successful or not is debatable - I have my own gripes on GDPR enforcement (I really hope the banners will get nuked out of existence).
https://www.cer.eu/insights/europe-has-produced-tech-champio...
https://www.investeurope.eu/news/newsroom/state-of-european-...
The tech sector represents 15% of EU's GDP. I currently work in the tech sector in europe, there's no shortage of companies hiring (both startups and enterprise), and anecdotally, from my personal network, enough startups are surviving the 5 and 10 years mark that I'm pretty confident there's enough new ideas/companies (as opposed to only having old/legacy enterprises) to ensure the good health of the sector.
Now, I will acknowledge that funding is more complicated in the EU compared to the US - but that's something that has been acknowledged by EU leadership and is being actively worked on. The Draghi report lays out a vision for how this can be achieved, with recommendation on what steps to take to achieve that vision. https://commission.europa.eu/topics/competitiveness/draghi-r...
So yeah, the tech sector is still well and alive in the EU, and there is reason to believe that it's going to get in an even better position.