There's a lot of pressure from external sources - the EFL, the political sphere etc for the PL to better regulate clubs and their spending. The idea initially was to prevent clubs going bust, but that was just a cover for essentially protecting the historic elite. Now it's all an obsession over profit and loss but doesn't perhaps provide enough mitigation for clubs going up and down the leagues or having external issues and it's creating uncertainty over the actual league table and what it might look like once punishments/appeals have been dealt with.
You've got the wider pyramid struggling to make ends meet whilst the PL clubs, particularly at the top, are pulling further and further away.
The caps elsewhere in Europe and with UEFA are stricter so the PL shouldn't decline. But it depends whether the product remains as attractive. If things are impacted and revenues drop so will the amount the clubs can spend and it will lead to a decline in the future. Right now that's not a risk, but we'll see how long it lasts.
In rugby it's not had any benefit. You've even got English players who sacrifice an international career to go and make money abroad. Similarly with cricket. Again, not a risk currently in England but again perhaps in the future.