But the thing is - the reason large companies often don't give folks like you and me these things is becuase there are proven reasons to do the contrary that actually end up making them more money. It sucks, but it's reality.
1. "Call us" pricing works because for big enterprise deals (4-7+ figures), there's often some serious negotiation involved and if you just show a sticker price up front, you risk a) scaring the buyer because the price is too high, b) losing the buyer because your competitor will just negotiate a better price than your listed price or b) leave yourself no room to negotiate if you really put your best price on the website.
2. Offering immediate free trials where you can jump in right away is the ideal world for nerds -- again, I love it personally. But software is often complex, and a guided demo/implementation is often the best path to make sure your buyers are actually successful. Otherwise you risk a lot of folks who sign up, jump in, have no idea what they're doing, and then abandon the trial immediately and go to a competitor who held their hand.
3. "Let me sign up right away and start using your product for $0..." If only offering Freemium were so simple. You will immediately have to deal with porn (it's always porn - and often kiddie porn. These people will figure out incredibly creative ways to use your SaaS product to host illegal content one way or another), spam, fraud, customer service issues, etc. There are many valid reasons to offer Freemium. There are many valid reasons not to do so. It's just not so simple.
4. Again, think about the flip side here. Lower friction to sign-ups without a card, but SO much hassle when it comes time to pay -- now you have to nag, bug, etc. to get payment, and then you have to delete accounts that are dormant. And you have much lower buying intent signals, etc. etc. etc.
I wish the world of software catered to folks like us, but I fully and completely understand why it doesn't.