it weren't western weapons that made the Black Sea unsafe for the Russian Navy

Not true. What little success they had there was due to British naval drones. Those worked for a while until Russia adapted. Now you hardly ever hear of success anymore.

Ukranian drones did it.

Again, technically not the case. Most of them are Chinese, the Ukrainians just strap explosive shells on them.

the war on the actual frontline has become drone-heavy

Drones play a large and vital role but they have not and cannot replace the role of conventional artillery. In fact the most effective use of drones in this conflict has been as artillery spotters. The reason why Ukraine relies on kamikaze drones to such an asymmetrical extent is because they have little else left by now. It is done out of necessity, not because it is the optimal thing to do.

Further, there is a certain inherent bias in OSINT toward overestimating the impact of drones on the battlefield due to the fact that they come with their own video footage whereas an artillery shell does not film as it flies toward a target.

Ukraine started this war with their pants down

Not really. Ukraine had the largest and best equipped military of any European country except for Russia at the start of this conflict. They were involved in an active conflict since 2014, had tens of thousands of soldiers already deployed and large swathes of the eastern front heavily fortified, and they had been receiving training from NATO for years as well as weapons.

Then they were further pumped full with all remaining Warsaw pact equipment that could be scrounged up (which was actually a very large amount) when the conflict began.

and indeed if it weren't for western systems and ammunition they would've lost it long ago

This is true.

at the same time they've been building up their own military production and becoming more and more independent

Quite the opposite. Ukraine began this war with far more of a military industry than it has now. It lost almost all of it to Russian strikes, and what is left are almost exclusively small scale decentralized production which can only produce small weapons (drones first and foremost) and ammunition but nothing on the scale of tanks, artillery systems, air defense systems, etc.

Ukraine is now more dependent on western supplies than it has ever been, and not just in the military sphere. Its entire government is being kept afloat by US and European money which pays the salaries of virtually everyone in the Ukrainian government. It even imports energy. Functionally Ukraine's economy is dead.