Has there been "decoration inflation" over the last couple of decades?

The scope of what the military is asked to do has increased as well. Humanitarian missions, more training overseas, etc. there are valid reasons these exist.

I think the real issue is that some people get awarded things that they dont deserve and others perform well above their grade and get little recognition for it.

There are a lot of ribbons and medals that military members may earn. I retired in 1991. In the decade before I retired we saw the addition of the Achievement Medals for all Services and Joint. The addition of Joint awards equivalent to the Service awards, for example the Defense Meritorious Service Medal, were added. And, everybody's favorite each Service's training ribbon. That's one that just showed up on my personnel report one year because I had completed Pilot Training. I was already a Major when it appeared on my records. Then there are "been there" ribbons. We increased those by several with the wars in Iraq, Afghanistan, Bosnia, and other locations in the last 20 years.

The Services use ribbons and badges differently adding to the proliferations of things on the uniform. All of the Services except the Air Force use stripes on the sleeves to denote years of service and years of overseas service--Navy and Marines enlisted only. The Air Force uses ribbons (longevity, overseas short tour, and overseas long tour). The Army and Marines use badgers to represent marksmanship skills. The Air Force uses a ribbon. The Navy denotes specialty (rate) for enlisted personnel with a symbol integrated with their rank. The Air Force denotes enlisted and officer specialty "communities" with a badge, e.g., maintenance, finance, civil engineering, medical technician, nurse, doctor, medical admin, supply, air battle manager. These badges except for aviation and professional corps were added in the 1980s. The Army uses a Branch designation, e.g., infantry, aviation, logistics, on enlisted and officer Service Uniform lapel. All five uniformed services award qualification badges, such as pilot wings, paratrooper wings, or combat medic. The Services decided they needed to give officers with command experience their own badge, so they all developed their own "command star" that is generally worn above or on the right pocket of the shirt or service jacket.

I believe you are correct in saying the uniformed services have added a lot of stuff to the uniforms in the last 20 years. I would say in the last 40.

There aren’t that many new medals or badges. The Combat Action Badge-Circa 2004 or 5. The Army Achievement Medal-Circa 1983 or 4. A couple of Campaign or service ribbons but they come with conflict, peace Ops or War. I could be wrong.