The limits that have been imposed on work and I9 visa are going to have a negative effect on the technology industry. It's going to be harder to fill specific high demand, high skill technology positions. It's going be harder to recruit good talent and harder to keep that talent.
The US visa system can be a minefield, but there are so many companies that offer their services who know how to apply successfully, so the fee is worth it. If a company sponsors a potential employee, they usually find there are few issues, unless the person has a criminal record. Visas are never easy to get and the strict guidelines are there for a reason, otherwise too many people would get visas.
The current visa requirements protect the time and money invested by tech workers for specific skills. Remove the protection of the visa requirements and you remove the value and reward of keeping on top of given technology needs. The current market structure is providing a good return to investment for skills. If there is a shortage of a given skill in the current market the value of that skill increases which in turn increases the number who seek after these skills through new training and investment.
I think at this point, it is safe to say that the Tech industry is here to stay and is not going to have much negative effect brought on it. Even something as major as the U.S. Visa requirements will most likely have close to no effect at all on the Tech industry.