I interned in high school at Brookhaven National Lab working on a team that analyzed STAR (Solenoidal Tracker at RHIC) data from RHIC (Relativistic Heavy Ion Collider). I didn't contribute all that much as a high school intern but the program director said at the end that he liked the high school program because he wanted to help funnel and bring people back to help build up the labs.
My experience was that everyone there was extremely smart, but all post-doc and top scientists in their field (the team I worked on was looking for Anti-Alpha particles from gold-gold particle collisions that also helped create Quark Gluon Plasma). So I'm not sure their relative need for regular software engineers.
In terms of bureaucracy, you're still working for the government. The scientists all complained about the layers of government bureaucracy but were mostly okay with it. High-tier science moves at a pretty slow pace; coming from a tech background you might not be used to the slow pace around the actual physical construction of some of these devices, let alone the fund-seeking, approvals, testing, runs, and data collection. and 33-50% is a hopeful estimate. Let's say one is a 500k a year senior/staff SWE at FAANG. at a similar level of experience, one's pay would be very lucky to break 150k.
So fascinating science, layers of bureaucracy, slow moving stuff, PhD's in their fields, and reduced pay. Again I was only a high school intern, but I spoke with the scientists about their experiences so take my recollection with massive salt. I walked away from the summer fascinated by the work and I had a love of physics at the time; but I also left (this was 2010 IIRC?) watching the world of tech explode at a massive pace and thought that I didn't like physics enough ( I had spent my junior/senior year of high school doing a capstone project on theoretical physics and having taken a lot of physics classes). When I went to college the next year, I tried a few engineering courses, and switched to CS. I'm glad I made the switch.