How long has Russia been trying to fight and losing against a small country with basically no military budget?

There is a war of attrition in which Russia is winning by most important measure of gaining vs losing territory. It has equipment superiority over Western backed Ukraine. Production capacity that is higher than the west.

The US Military industrial complex is MASSIVE. In a real conflict, it can easily pivot to more effective technologies

While massive, it is extremely wasteful, and the technology shifts it has committed to are expensive and underperforming. F35s have low reliability/flight time. Littoral ships scrapped 5 years after comissioning, refueling ships in long dry dock time. Boeing troubles is a hallmark of a US defense system that only cares about spending money instead of results/quality/value, with CEOs simply good at bribes and promises instead of caring about execution.

It’s cope. It means nothing. Speculating on the effectiveness of warfighting technology before a peer engagement is just flag-waving. A stealthed craft deploying guided munitions at half a mile is a lot less likely to be countered when compared to a medium-range ballistic missile from 30mi out, for example, despite the risk of a manned craft behind enemy territory. On a cost analysis, we can’t speculate on profitability until we know just how many of those munitions will be screened during an engagement. You fire 100 $5k rockets vs. 2 $250k cruise missile, the benefit only comes from the amount of bang that reaches the target.

One path to avoid MAD is through a limited strike on US. Missile defense systems theoretically protect from such strikes, though perhaps not from coastal sub strikes. A single nuclear strike on US collapses the country. With multiple theater wars/enemies, port detonations have no certain accountability for the strike.