Tax return deadline: are you late for a very important date?

I have two beefs about the tax return, some years back, I hoped to trade enough shares to need to make out a return, but never got there. However, I had asked for a form, just in case. I then received a reminder that I had to fill it in, which I duly did, and each year the return was demanded. I found it so difficult to collect the slips, collate the info and calculate the nets, grosses and totals that several times I dropped it off in the early hours of the Monday after the deadline. They then announced that they would block up the letterbox at 00:00 hours precisely, which they actually did. The next year, I only made it by 23:54, passing a number of anxious people on the stairs, both as I went up and came down.
The next year, I assembled all my slips, then tried my login 10 days early, which did not work. The site crashed, and I could not get any reset. I wasted hours trying to phone for help, and sent several emails explaining that I could not get in. It finally allowed a password reset late on the last night. I filled in the form online, got dumped out before midnight and added an explanation as to why it was beyond my control due to their extensive delays and asked not to be fined the £100 late fee. I had a nervous few days, then read in the papers that as so many people had been affected, no fine would be levied -what a relief! Weeks later a familiar buff envelope marked H.M. Tax appeared. The bold heading stated that I WAS to be fined £100 for failing to meet the statutary deadline. The A4 sheet was almost filled with writing explaining the law relating to the fine, how to pay it, the consequences for not doing so, and the statutory results including court action and how they would take the money if I did not pay. I got more and more wound up, until about an inch and a half from the bottom of the page, it stated “Amount to be paid £0.00”.
I continued filling out the forms each year, gradually moving submission dates back to well before Christmas. I then had a query, so went into my local tax office (which they have since helpfully moved way up north) and they answered my enquiry. As I was leaving, I asked why I had to fill in the form each year as I paid PAYE on all of my income , and all interest and dividends were taxed at source? The answer – ‘Because I had asked for one some 10-12 years before’ – I quickly asked ‘how do I get released from this?’ to be floored by the answer ‘just ask not to be sent one’ so I did so there and then.
Just how much grief was that and how much did that cost us tax payers, and for what? I even once had a notice that I was to be reviewed, no-one suggested it would be unnecessary to keep filling in the return and nearly every year I actually had a refund as they never allowed a legitimate rebate on my professional body fees.
They don’t seem to want to make it simple, and from other exchanges with them, I suspect there is some incentive (or bonus?) based on how much they demand from people, without taking into account whether that is actually justified and not later cancelled. In one case I was made to pay them a four figure sum because I had put a submission on the wrong piece of paper, despite asking them if it was correct. It was re-paid much later with interest, but it was a time when that was alot of money and we had an eye-watering mortgage interest rate, so it doubly hurt.