WOW - really really nitty.
...Nitty BR is good. It's safe. If a player doesn't wish to make multiple deposits or plans on not having to deposit ever again, then they need to follow a nitty BR plan.
It would also depends on the type of player you are. If you're a casual player playing 1 MTT a week, then you probably don't need 150+ buy-ins. If you plan on grinding multiple MTTs a day, say 20+/day, then yes, the more buy-ins, the better.
If you need to play 100 sng's before you win - you are a terrible player and should quit!
...You need multiple buy-ins for SNGs because if you're looking to make a profit and/or move up in stakes, you need to put in a ton a volume. It's not about winning 1 SNG, it's about profiting over a large sample size. No one ever wins 1 SNG and thinks they're ready to move up.
If you're looking to play multiple tables a day to increase your volume and $/hour, you need more buy-ins to multi-table comfortably.
If you are playing as a rec player and have no interest in becoming good, then go ahead and put all that money in your roll. BUT - a winning player only needs 20 buy ins
...You have this backwards. If you're a recreational player who doesn't put in a ton of volume, then you might only need 20 buy-ins for SNGs or MTTs because you aren't playing a ton where the inevitable downswings will affect you.
Any winning player that grinds SNGs/MTTs will tell you that one of the keys to success is following a good BR plan. The higher the buy-in, the harder your opponents are, the bigger the BR you'll need. It doesn't matter how good you are, variance will hit and if you don't have proper BRM or think that its impossible to go on 20+ game downswings, you're mistaken.
I can not repeat this enough times - if you are needing more than 20 buy ins to win anything you are in the wrong game - ONLY exception is if you only play mtts - with really big fields...and in this case if you do not cash one out of 50 times then you should not be playing - or you should not care that you are no good at the game.
...I've said this multiple times in this forum, but one of the biggest online MTTers, Shaun Deeb, once went on a 50 game downswing. And he plays the biggest buy-in games online. So, you're telling me that if a top online MTT pro can go on this big of a downswing and doesn't cash, they should stop playing?
Also, cashing 1/50 games in not even an indicator of skill at all. Assuming you mean min-cash, what is cashing going to do if you're stuck 49 games? You're still likely negative.
How to get good you say without playing - STUDY FIRST. In my early days I would read for an hour before playing any session - even if its a book I read before - then after your session review what you did - then read some more - then maybe even watch people play (boring BUT effective - believe me).
...Studying is just the tip of things. You still need to know when and how to apply what you've read in a game. I can read a book on Krav Maga for hours each day, but if I ever get into a fight, I probably wouldn't know how to use it effectively.
It's a combination of studying, playing, and knowing how to find and correct your leaks. Sometimes, those leaks aren't easily recognizable, so coaching is also an option. It really depends on where you are as a player and where you want to end up. Even the top players get coaching.
If you want to put in more then whatever - BUT again - a winning player only needs 20 buy ins.
...Again, this isn't a true. A winning player might only need 20 buy-ins, but they know its much better to keep many more buy-ins in the BR because variance and downswings are inevitable.