The founders and my immediate boss at the first startup I worked for were convinced huge corporations would see what they were doing and just beat them to the punch. Only years later after one of the huge corporations bought the business and they could see it from the inside did they understand that was never possible. At the startup you'd set three people working on something important and get it done the same day, at the huge corp there'd have to be a week or so of meetings to even assign people. Sure you could assign thirty or even three hundred if you needed them, but you're already a week late.

So don't worry about it.

Also once people we’re assigned it would be implemented by people who were (normally) not very good and could take months or years by the time they were finished because of all the extra features that weren’t actually needed were implemented and by the time they had changed frameworks, languages, tools and actually been deployed

Just ignore it. If your product is good enough and the market is big enough, you’ll be fine. If neither is true, you would have failed anyway.

If you're selling tech: they'll often rather buy you than spend time solving the problem themselves. Most things can't be sped up by a linear factor if you apply more money/people/resources, so they'd still need some time to catch up to what you do. Granted, they'd need less time, because they could do development, marketing, infrastructure etc in parallel, but still: they'll usually prefer not wasting that time and acquihire you (and your team), to go to where you are in a very short time and have domain experts on the team immediately.

That changes if there's a lot of competition of course, they might buy your competitor and throw their weight behind them.