I’ve been saying for years that a Zerg who goes mutas can’t establish a fourth and dies to the most basic bio tank timings. Have you seen Maru vs Solar game 1? Case in point. If you go mutas, the terran is free to push and end the game. It’s literally that simple. People complain about mutas, but they are in solid “meme build” territory. I make mutas to style on people. Terran is already spamming the counter to mutas en masse long before mutas get out. The fact that people lose to these units is amazing.
You always have to rush out baneling speed, followed by 1/1, if you want a fourth base and then you must go for hive because you are always behind in upgrades and ultras equalize that upgrade difference. If you go for delayed mutas instead of hive, you are massively behind in upgrades and you just go bankrupt from how incredibly badly your ground army trades. Getting out ultras is much more important than starting 3/3 upgrades.
You never dedicate any kind of gas to any kind of harass because the baneling is trying to bankrupt you at every waking second and you just can’t afford to go on the offensive. Zerg gets out ultras and counter pushes and that’s their one chance at winning the game. After that point it’s mass ghost and highly favors the terran. If you try to harass using gas, it doesn’t cause any delays in the short term production of terran because he’s already paid for those units – it’s the FUTURE production waves that are hurt. In the immediate time-frame you’ve hurt your own army by losing gas on harass. Terran’s offense is so incredibly strong that zerg just can’t afford to harass.
Zerg is stuck on tier 1 units all game vs a terran who can get out BCs at the 6 minute mark. This is why Zerg requires a level of strategic genius that is unparalleled in Terran/Protoss. If a Terran had to find a way to beat a zerg who has broodlords by only using marines, every terran in Grandmaster would lose 2,000 mmr. Terran “strategy” is “follow basic build order, do bio push and rally marines at the push, and do basic split micro.” Amazing. How can SC2 even be called a strategy game? The most strategy that terran has is deciding what path to take when doing his bio push. 
Don’t even get me started on game #2. Mass ghost is now beating mass baneling and mass lurker. It was literally just ghosts and medivacs. Lmao. Who could’ve seen this coming? Oh wait, I did. I wouldn’t even care if it took skill to do. Watching ghosts spam snipe is perhaps the least interesting unit dynamic to ever exist.
EDIT: I just saw the final game. Lmao. You never, ever, attack a terran. Beating terran is about base denial. When 2 siege tanks can kill an infinite amount of zerg, there is no way to force him out of the game. Denying bases is the only way to beat terran and this is true no matter how far behind he is. You could have 500 supply and he could have 5. You NEVER attack a terran’s main base.