"the law of the land" is a really shitty argument for supporting something when its questioned. its an unfair burden on small businesses. large enough ones probably get enough business it makes sense to install.
Society had this debate in 1990 and it was more than a super majority that supported ADA. You're welcome to go look up about that debate that made it the law of the land, many people on this board are old enough to remember it. I promise you that people brought up the burden on small businesses back then too. It's not even a hard calculus to make if you're starting a new business. Is it worth it for me to open my business while paying the costs to ensure that everyone has reasonable access to my services. If you choose to put in steps, or have an old building with steps then you can decide the tradeoffs. If you're renting you can probably negotiate those costs with your landlord as the improvements will continue beyond your lease. These aren't surprise costs, they can be made ahead of time to decide if you have a viable business.
I've always wondered about stances like this: if the US economy ever falters will you consider whether these extra costs could have an impact on it? If enough people run the calculus that the business isn't worth opening then you end up with communities that don't have businesses serving them.
Villages in my country are losing their only stores because the stores don't get enough business to make it worth the cost. These are usually villages with a high average age. What happens to the residents? Many of the elderly don't have a car. They can't exactly go over to the next town and buy a week's worth of groceries if they can't carry these.
The store closing essentially kills off the village over time. Heavy additional costs to doing business can mean that a community just goes without any service at all. It might not be a common issue now, but if it ever does appear then it's not like you can turn the economy back on like you would flip a switch.
Do they have an impact? Sure. Are they large? In most cases no. A well kept and safe building is usually not going to have much trouble getting compliant. And once it’s compliant there isn’t much upkeep. If a business shuts down because of ADA costs, what is more likely is the building has major issues and it’s not worth throwing any more money at it. It’s a dying business.
Also, there is no ADA compliance inspector. One of their customers would have to sue or report them. If they get reported then the remediation is to come up with a plan to address the concerns in a reasonable time. You really only get in trouble when you start willfully refusing to address issues. Again, businesses have had decades to address these. If they close and kill a town now, it’s because they didn’t do the right thing when times were good for them.