As an engineer, boom/bust cycles like this remind me of system instability with insufficient damping. It doesn't work itself out; the oscillations get larger and larger, and then something breaks. Remember the Tacoma Narrows Bridge?
They are getting larger. You're looking too far back. After the Great Depression, policies were enacted which served as dampers to improve system stability. They worked for quite a while. But eventually these policies were eroded or repealed, and other societal factors came along which degraded stability, so the oscillations picked up again, and grew larger and larger (think 80s S&L crisis, '00 dot-com crash), culminating in the '08 recession. Now we're going to have a much bigger one with Trump and the GOP in office. If this one doesn't cause a collapse, the next one will.
The dot com crash was big for the stock market and for the tech industry, but it wasn't a really big recession; it barely touched economic fundamentals, just look at GDP.
Personally I doubt the next recession/slowdown will be anywhere near as big as 08, but I guess we'll see.
We always have recessions when there's Republicans in power (I'm not sure why voters haven't figured this one out yet); there was one with Reagan, one with Bush I, one with Bush II, etc. Trump and the current crop of Republicans are advocating very extreme changes (namely trade restrictions), so I think we're likely to have a more extreme recession because of this.
