"If I only had "x" my track would sound so much better...."
Yes, we've all said it at one point or another. There is a perception that the gear used makes the biggest impact on the quality of the sound. A great mic makes a great vocal, a great amp makes a great guitar sound, a great drum kit makes me sound like so and so...
It's a misconception everyone has fallen to at one point. Even when I was starting out, I would search and make wish lists of incredibly expensive gear. Hoping one day I could get my hands on it, and I would sound so much better. As I started acquiring pieces of gear, a realization started to sink in... I sounded the same! The gear wasn't providing the "Magic" I thought it would. Somehow, the gear I purchased didn't make me sound "better", in fact I sounded worse! How could this be?!?!
Something I was lucky to learn early on is gear doesn't make the engineer. In fact, if you don't understand how to use the gear, you can end up making things worse!
"But Insert Name Here uses "X" piece of gear, and their mixes sound amazing!"
Yes, their mixes do sound amazing, but the gear didn't "magically" make that happen. The engineer made the mix sound amazing. The gear is there to be used. It's a tool, just like a wrench for a mechanic, or a paint brush for a painter. Some tools help you achieve your goal faster, but it doesn't do it for you. Having the understanding before you start using the tool is the key. If you do not understand what you are trying to accomplish and how to get there, then you won't be happy with the end result.
"So what is an engineer to do? How am I supposed to learn this gear without owning it?"
Well that's the kicker. You might already own it, or at least some version of it. No matter what DAW you work in, they all come with stock plugins. Most of these plugins are modeled after pieces of analog gear. Especially the classic and most used studio pieces.
"But plugins don't capture the 'Analog' sound of the real thing!'
Have you used the real thing? How many different versions of the same piece of gear have you tried? The best thing about plugins, they are each modeled on different pieces of the same style of gear. In the hardware world, no 2 pieces of gear are perfectly matched. Even the two 1176 compressors we have in the studio sound different at the same exact settings. This is something you have to learn about hardware, all the components inside have tolerances. Each little piece can be slightly off than the next one. These non-linearities is what makes that 'Analog' sound. With the digital world today, most companies have modeled analog gear quite well.
The best thing you can do before going a spending a bunch of money on new gear, is to learn what you already have. Sure, there might be a cooler or different sounding version out there, but don't get caught up in the hype. As you learn the how to use what you already have, you will get better at your craft. Eventually you will have acquired knowledge to make an educated decision on your next gear purchase, instead of a lustful one. Having knowledge of the sound and style you're going for, and understanding how to get there will lead you in the right direction.
Remember, it's just a tool to be used. If you don't understand how to use it properly, then it might not be what you need at that moment.
Now go make great music!