I would say achieved for market share (as is the case here) and acquired for customers or clients.

If you wish to have a literal translation, go with acquirable. In this context however, the actual term is "addressable".

https://corporatefinanceinstitute.com/resources/knowledge/st...
The Total Addressable Market (TAM), also referred to as total available market, is the overall revenue opportunity that is available to a product or service if 100% market share was achieved. It helps determine the level of effort and funding that a person or company should put into a new business line.
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In a nutshell, this means that the company might obtain a 15% share of the addressable market, estimated to reach a worth of 100M Euro in the 2021-2023 three-year period. Also see: https://en.wikipedia.org/wiki/Total_addressable_market

Italian term (edited): si ritiene acquisibile

> needs to collocate with si ritiene and, statistically in percentage terms, con una significativa probabilità circa il 15% so, alternatively, as a matter of style: is considered achievable.

I 'deemed' that si retiiene is cognate with the French of 'se retenir pour..' assumed to have the same meaning of estimated.

I think this term best captures the sense that other translators have already described ("Can be acquired"/"acquirable"), but "obtainable" is perhaps more common in general English usage.