You have literally no idea if this is true. Literally used in the literal sense because until such microbes exist you can't predict their behavior.
Polyethylene for example is a long string of hydrogen and carbon. (CH2-) Microbiology requires more than that for replication. It’s the same reason dry sugar does not get consumed by microbes.
And any opening or crack which rainwater or groundwater or seawater or dust can occasionally access will carry nutrients required for microbial life.
You literally can't. History shows us that introducing new species with novel abilities to an ecosystem has far reaching, unforeseen, often devastating and usually irreversible consequences. Why would we risk this? Plastic digesting bacteria would be utterly novel and completely outside our control.
Edit: oh and the table is almost certainly treated with some chemical agent that helps preserve it. Be that paint or varnish...
Life needs to obey physics and thus chemistry. Many plastics are already consumed by various bacteria in specific environments yet function perfectly well as TV remotes etc.
Further, plastics have a rather wide range of chemistry. Polyvinyl Chloride (PVC) for example includes a lot of chlorine making it much harder for organic chemistry to deal with. Thus making it suitable for wet environments.
PS: Indoor wooden tables are coated in varnish largely to aid in cleaning and protection from ware. Kitchen cutting boards last for years demonstrating the difference between intermittently damp vs long term wet conditions.
You literally can't know what the consequences of plastic metabolism would be. History shows us that introducing new species with novel abilities to an ecosystem has far reaching, unforeseen, often devastating and usually irreversible consequences. Why would we risk this? Plastic digesting bacteria would be utterly novel and completely outside our control.
To make confident predictions about species that don't even exist yet is just hubris.
I am willing to wager rather large sums of money they are not going to violate the conservation of energy. Unknown, does not necessarily mean unknowable.
That said, I said nothing about their impact on ecosystems just the majority of plastics in use by humans.